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the thermometer attached to it was o°8 during the whole perturbation.

The magnetic instruments I make use of are those of the Observatory of Makerston, Scotland, which were arranged and sent many years ago to this Observatory by order of General Sabine at the request of P. Secchi, of the Roman Observatory.

Another perturbation, although not so intense as those already described, was observed on the 2nd of November. It began at ten o'clock in the morning, and lasted the whole day.

A very remarkable one was also observed on the 17th and 18th of June; it began at ten o'clock in the evening of the 17th.

On the 21st of August, while a hurricane was felt in St. Thomas, and an aurora borealis seen from the Observatory of Dun Echt, Aberdeen, I noticed an extraordi

MAGNETICAL AND METEOROLOGICAL OB- nary variation, which attained its maximum between four

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SERVATIONS AT HAVANA

N the 9th and 10th day of November I noticed on my instruments two strong magnetic perturbations, during which a series of extraordinary observations was taken at intervals of five, of ten, and fifteen minutes. From these I was naturally drawn to think that an aurora borealis would be seen in higher latitudes, and was waiting for a confirmation of my views.

This I found in the numbers 16th and 23rd of November of your scientific journal, NATURE, which I have just received, and in which I see with great pleasure the

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Each one of these divisions of the scale corresponds in parts of horizontal force to K=0'000099573.

description of the aurora borealis seen in England on the 9th and 10th of November in perfect accordance with my observations of those days.

and six o'clock in the afternoon. A similar one occurred on the 24th.

Finally, on the 16th and 17th of August two great hurricanes swept the shores of Florida, and their influence upon the magnetic force can be perfectly noticed on the curves of those days. BENEDICT VINES

Havana, Dec. 21, 1871

NOTES

WE alluded some time since to the threatened destruction of one of the most notable megalithic monuments in this country, the Great Circle at Avebury, in Wiltshire. All archeologists will be glad to hear that Sir John Lubbock has added one more to his eminent services to science by the purchase of the site on which the Circle stands. It is right also that the meed of praise should be awarded to those of the residents in the district whose zeal has been directed towards the attainment of this object, and who have thus shown their sense of the value of the monument which is one of the glories of their county. We refer especially to the Rev. Bryan King, the vicar of the parish, Mr. Kemm, Mr. George Brown, and the Rev. Alfred Charles Smith, Hon. Secretary of the Wiltshire Archæological and Natural History Society. It is to be hoped that their example will stimulate similar zeal for the preservation of monuments in other parts of the country.

DR. T. STERRY HUNT, chemist to the Canadian Geological Survey, has been appointed to the chair of Geology in the Massachusetts Institute of Technology.

MR. HENSMAN has been appointed Lecturer on Botany at the Middlesex Hospital, in the place of Dr. T. S. Cobbold, F.R.S., who has received the appointment of Lecturer on Parasitic Diseases.

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AT the meeting of the Royal Geographical Society on Monday evening last, Sir Henry Rawlinson, the President, announced that the vessel with the Livingstone Expedition on board arrived at Malta on the 23rd inst., and was to reach Port Said on Sunday, and leave Suez on Monday night. By the accounts to hand all As it will not be devoid of interest to know to what on board were pronounced to be well, and in the highest spirits. an extent an aurora borealis, when seen in England, The finances of the expedition were in a highly satisfactory state, exerts its influence on the magnetic variations of a place many contributions being remarkably striking, as showing the situated in the Tropics and in very remote longitude, I great interest taken in the enterprise not only in this, but in many take the liberty of sending you the curves of the hori- distant countries. A contribution of 100 guineas had been rezontal magnetic force as registered by the bifilar magneto-ceived from a former member at Stockholm, who had always meter on the 9th and 10th of November, together with the curve of the mean horizontal force of the whole month. A comparison between them and those taken in other places will be, I hope, very pleasant to those who are interested in magnetic researches.

My observations on the bifilar magnetometer are reduced to the temperature of 77° Fah. The variation of

taken a deep interest in the travels and discoveries of Dr. Living. stone. The Italian Royal Geographical Society had also sent a contribution of 157. 15s., while national committees to assist the fund had been formed in Scotland and Ireland, who were working most energetically. The town of Glasgow has subscribed 1,000l., Edinburgh 400/., and Dublin promised to be equally

generous. Similar interest had been awakened in Chicago, whence 100/. had come in to be placed at the disposal of the Livingstone Expedition; and on the whole it might be said the announcement of the undertaking had been hailed with general satisfaction throughout the civilised world. Exclusive of two sums of 4007. and 600%. odd, the latter the balance of the former Government grant, there was now standing to the credit of the expedition a sum of 4,200.

THE following gentlemen were on Saturday last elected to Junior Studentships in Natural Science at Christchurch, Oxford-M.D. A. Greswell, Commoner of Balliol College, Mr. B. Hainsworth, of Manchester Grammar School, Mr. W. A. Smith, of Clifton College. These scholarships are of the annual value of 75%., together with the rooms rent free.

AT the examination recently concluded at the Melbourne University, there were no less than 225 competitors, of whom 86 passed the matriculation examination, and 108 the civil service examination. Many of the names in the former were included in the latter, but on the other hand, there were some who passed the larger, the matriculation examination, who did not pass the smaller examination, that for the civil service. The reason is, that for the matriculation any six subjects serve to qualify, while for the civil service, of the four subjects, two given ones are essential. The examinations this time had a novel feature, from there being three lady candidates, all of whom passed. The Council of the University, however, has passed a resolution to the effect that the successful ladies should not be allowed to matriculate. No reasons have been given for this decision, but it is presumed that the obstacle is a legal one.

THE Academy states that the President of the Geographical Society of Italy has written to the papers to say that the Conservator of the Bibliothèque Royale of Belgium has discovered a MS., in twelve chapters, containing the original autograph account of the discovery of Australia by Manuel Godinho, a Portuguese navigator, who touched there in 1601, and whose priority to the Dutch sailors, who arrived three or four years later, has been unduly neglected. Mr. Ruelens vouches for the authenticity of the MS., which was brought to light at the Antwerp Exhibition, though it passed unnoticed in the crowd.

Prof. ClevelaND ABBE, in an article entitled "Historical Note on the Method of Least Squares," in the American Journal of Science and Arts, shows that this method, though first published in a printed form by Le Gendre in 1806, and invented by Gauss in 1795, was published in 1808 by Prof. Robert Adrain, at that time in New Brunswick, N. J., in the "Analyst," he having been independently led to this invention by the study of a prize problem offered some months previously in that periodical.

AN important addition has been made to the list of works devoted to inquiries and instructions in regard to the great fisheries in the form of a paper, by M. Achille Costa, upon the fisheries of the Gulf of Naples, published by the Royal Institute for the Encouragement of Natural Science, &c., of Naples. The subject is treated under four heads: first, a description of the various modes by which fishing is prosecuted in the Gulf of Naples, whether commendable or otherwise, with engravings of the nets and other apparatus used; second, the consideration of the various modes of fishing, and their relationship to the present and prospective supply; third, memoranda in regard to the localities in which the different kinds of fish and other marine animals are to be found, and the favourite places for depositing their spawn; and fourth, a systematic catalogue of the different species of marine animals found in the Gulf of Naples, and gathered for the purpose of serving as food.

PROF. MARSH reports to the American Journal of Science the

discovery, during his explorations in 1871, of a remarkable fossil bird. It was found in the Upper Cretaceous of Western Kansas, and the remains consist of the greater portion of the skeleton, at least five feet in height, and which, although a true bird, as is shown by the vertebræ and other parts of the skeleton, differs widely from any known 'recent or extinct forms of that class, and affords a fine example of a comprehensive type. The bones are all well preserved. The femur is very short, but the other portions of the legs are quite elongated. The metatarsal bones appear to have been separated. On his return the professor proposes to describe this unique fossil under the name of Hesperornis regalis.

IN the expedition against the Losshais, who have attacked our tea plantations in Cachar, the interests of science have been cared for. Lieutenant Browne, 44th Foot, known in India as an able naturalist, has charge, with a trained native from the Indian Museum at Calcutta, to act as collector. Something is expected from the unexplored regions of the Losshai country.

HERR PAUSCH, a member of the late German polra expedition, recently made a communication to the German Anthropological Society in regard to certain abandoned habitations of the Esquimaux in East Greenland. He remarked that at each of seven different points they found three stone houses, some of them certainly over one hundred years old. These were winter huts, the remnants of their summer abodes being indicated by stone rings. In many places there were indications of stone graves, and from the skeletons found in them tolerably wellpreserved crania were obtained, agreeing with the Eastern Esquimaux type as described by Virchow, and exhibiting the carnivorous habit in the highest degree. Remains of wood carving, tolerably well executed, occurred with the dead bodies, and in the heap were found bone knife-handles, harpoons of bone, arrowtips, and even knife-shaped pieces of iron, probably obtained from the English expedition of 1823.

IN referring to the explorations of Dr. Hayden about the Yellow Stone Lake during the past summer, mention was made of the fact that the trout all seemed very much infested with a peculiar kind of worm, which interfered considerably with the enjoyment of eating them. Specimens of this animal have been submitted to Prof. Leidy, of Philadelphia, who reports that they represent a new species or type of worm, of the genus Dibothrium. Two species of the genus have long been known as infesting salmon and other members of the trout family in Europe, but both are decidedly different from the new form just mentioned.

THE Trustees of the Museum of Comparative Zoology at Harvard College, Cambridge, U.S.A., have issued their Annual Register for 1870, together with the Report of the Director, Prof. Agassiz. It is stated that the accessions to the Museum during the past year had been very great and of surpassing importance. Foremost stands Deyrolle's collection of Curculionidæ, presented by Mrs. A. Hemenway; next the collection of Galls of Baron d'Osten-Sacken, presented by him; then the magnificent collection of Fossil Plants of M. Lesquereux, especially remarkable for the exquisite selection of the specimens it contains, and that of Insects of Texas, made by Mr. J. Boll, both of which have been bought by the Museum; and not least the unparalleled collection of Neuroptera, brought to America by Dr. Hagen, and now deposited in the Museum. There are special reports on the Mammalia and Birds by Mr. J. A. Allen; on the Fishes by Dr. Franz Steindachner; on Conchology by J. G. Anthony; on the Articulata by Dr. Hagen; and on the Palæontological collections by Prof. Shaler, Mr. J. B. Perry, and

Dr. G. A. Macak.

WE have received the Register of the Trustees, Officers, and Students of the Lehigh University, South Bethlehem, Penn.,

66

U.S., for, the year 1871-72. The University was founded by a gift, in the year 1865, from the Hon. Asa Parker, of the sum of 500,000 dols., and a site of land containing 56 acres in the Lehigh Valley. The purpose of the founder was to provide the means for imparting to young men of the valley, of the state, and of the country, a complete professional education, which should not only supply their general wants, but also fit them to take an immediate and active part in the practical and professional duties of the time. The system determined upon proposes to discard only what has been proved to be useless in the former systems, and to introduce those important branches which have been heretofore more or less neglected in what purports to be a Jiberal education, and especially those industrial pursuits which tend to develop the resources of the country,-pursuits, the paramount claims and inter-relations of which natural science is daily displaying—such as Engineering, Civil, Mechanical, and Mining; Chemistry, Metallurgy, Architecture, and Construction." For this purpose, special classes in all the above-named subjects have been instituted; and by the liberality of Robert H. Sayre, one of the trustees of the University, an Astronomical Observatory has been erected in the University grounds and placed under the care of the Professor of Mathematics and Astronomy, for instruction of students in Practical Astronomy. The Observatory contains an equatorial, by Alvan Clark, of six inches clear aperture, and of eight feet focus; a zenith sector, by Blunt; a superior astronomical clock, by William Bond and Sons; a meridian circle and a prismatic sectant, by Pistor and Martins.

DR. E. ASKENASY, in his "Beiträge zur Kritik der Darwinschen Lehre," contrasts the doctrine of Natural Selection as carried out to its full extent by Darwin in his "Origin of Species" and "Variation of Animals and Plants under Domestication," with the modified form of theory adopted by Nägeli in his "Conception and Origin of Species in Natural History."

THE first part of Dr. N. J. C. Müller's "Botanische Untersuchungen" treats of the separation of carbonic acid by the green parts of plants under the influence of sunlight, and is illustrated by a plate, delineating, in the form of curves, the effects of the different rays in the solar spectrum.

Dr. Gerard KREFFT, in a paper on the Australian Vertebrata, Fossil and Recent, points out how valuable would be a general study of Natural History in a country like Australia, where every pool and creek teems with animal life, numerous mussels, various kinds of cray-fish, turtles, frogs, lizards, freshwater snakes, and other creatures, all of which are more nourishing to a starving human being than the wretched nardoo on which the lamented Burke and Wills tried to subsist. He advocates the establishment of district museums, and that the children should be taught to observe the habits and economy of different animals, in particular of those which are useful, by which means the wealth of the country would be much increased. Dr. Krefft promises hereafter a complete natural history of Australian Vertebrates, which will be the first ever published.

THE "American Horological Journal,” published in New York, of which several numbers lie on our table, contains not only articles of special interest to manufacturers and vendors of clocks and watches, but others on Spectrum Analysis, and kindred scientific subjects.

"INDEX TO PRICES" is responsible for the following:-The demand for human hair is so great that it is impossible to supply it. Price has risen to 16s. a pound. As much as 1,000 dols. has been offered for a "head of hair" six feet long. Some ladies dress fifty to sixty miles of hair every morning.

Ar the meeting of the Society of Arts held last week, Dr. Brands, Inspector-General of Forests to the Government of India, said that the cinchona plantations were now become almost

forests. Before long they would be able to be coppiced every six or eight years, just as oak coppices were treated in Germany, Scotland, and elsewhere, every fifteenth or eighteenth year, and this would probably be the simplest and most profitable mode of getting the bark. The introduction of ipecacuanha into India was also alluded to. Dr. Masters expressed an opinion that there must be dozens, if not scores, of plants indigenous to that country, having the same medical properties as ipecacuanha, which could be much more easily utilised.

ACCORDING to the editor of the Journal of Conchology, of Paris, the Paris Museum received twenty-three shots from cannon of the German besiegers in the course of the siege, destroying many of the plant-houses. Two of these balls exploded in the conchological laboratory, in the care of Prof. Deshayes, causing great injury to the specimens, and the Septaria in the general collection were literally ground to powder. The large collection of shells of the lower sands of the Paris basin was entirely destroyed. This is much to be lamented in a scientific point or view, as it contained many types. A ball also passed through a glass case containing the Unios and Anodonta.

AT a late meeting of the State Dental Society of Pennsylvania one of the members, Dr. Barker, is reported in the Dental Times (July 1871) to have read an essay on Irregularity of Teeth, the circumstances favouring it, and suggestions on its prevention and treatment. The essayist held the opinion that a retrograde metamorphosis is going on in human teeth. To obviate this there must be improvement in the mode of living, the use of more substantial food, and from the time of the appearance of the deciduous teeth children should be under the care of an edu cated dentist; so that when the permanent teeth begin to erupt they may be properly guided, and a regular arch result. As a rule the first permanent molars should be extracted to make room for the succeeding teeth, for the jaws of the Anglo-Saxon race are shortening, and no longer have room for thirty-two teeth. How will this end?

ON January 28, the town of Schamachi, in the Caucasus, was totally destroyed by a succession of earthquakes. Few houses remain standing, and many lives have been lost.

A CORRESPONDENT of the Globe writes to say that the recent intelligence, describing the total destruction of the city of Oran in Chilé by an earthquake, must be a mistake. He says, that the city of Oran in the province of Salta, in the Argentine Confederation, was destroyed by an earthquake, on October 22, last year, but very few lives were lost. This is the earthquake referred to in NATURE (p. 251), but the date was there wrongly given as November 15.

BETWEEN ten and eleven at night, on December 12, two shocks of earthquake were felt at Serampore, in quick succession. The second and the strongest lasted about ten seconds, and seemed to move from north to south. The vibrations were very strong, but no great amount of damage was done.

THE Rangoon Mail states that on the night of December 12, an earthquake which lasted about ten seconds was felt at Prome. The wave appeared to travel from north-east to south-west. The shocks were stated to be severe, and followed in quick succession, but no damage is reported in the town. The earthquake occurred on the night of the new moon. A letter received from Herzadak states that an earthquake was felt there on the same night. In another paragraph we give an account of an earthquake felt at the same time at Serampore.

On the 12th of December at 10.5 P.M. an earthquake was felt at Calcutta with a shock lasting eight seconds, and moving from east to west. It was felt at Ducca about the same time, but its direction was considered to be from north to south. It was also felt at Akyab and in Burmah.

WALLACE ON THE ORIGIN OF INSECTS*

egg a globular ciliated gemmule; elongation and segmentation then take place, always in the hinder part, so as to elongate the

AMID all the discussions to which the question of the Origin compound animal without interfering with the more specialised

of Insects has given rise, it is to me surprising that one of the most ingenious and remarkable theories ever put forth on a question of natural history has not been so much as once alluded to. More than six years ago, Mr. Herbert Spencer published, in his "Principles of Biology," a view of the nature and origin of the annulose type of animals, which goes to the very root of the whole question; and, if this view is a sound one, it must so materially affect the interpretation of all embryological and anatomical facts bearing on this great subject, that those who work in ignorance of it can hardly hope to arrive at true results. I propose, therefore, to lay before you a brief sketch of Mr. Spencer's theory, with the hope of calling attention to it, and inducing some of you to take up what seems to me to be a most promising line of research; and, although the question is one on which I feel quite incompetent to form a sound judgment, I shall call your attention to the light which it seems to throw on some of the most curious anomalies of insect structure.

The theory itself may be enunciated in very few words. It is, that insects, as well as all the Annulosa, are not primarily single individuals, but that each one is a compound, representing as many individuals as there are true segments in the body, these individuals having become severally differentiated and specialised to perform certain definite functions for the good of the whole compound animal.

Mr. Spencer first calls attention to the fact, that among the undoubtedly compound animals (which are almost all found in the sub-kingdoms, Coelenterata and Molluscoida) the several individuals are rarely combined in such a manner as to necessitate any physiological division of labour amoug them. The associated individuals of aHydrozoon or an Ascidian are each free to spread their tentacles, to draw in currents of water, and to select their food, without in any way interfering with each other, because the compound animal is either branched or approximately hemispherical, and thus there is no necessity for any of the combined individuals to become especially modified with regard to the rest. But should a compound animal have its component individuals arranged in a linear series, there would most probably arise a marked difference of conditions between the two situated at the extremities and those between them. If they remained united, some modification must have occurred to adapt each to its condition. But if, further, the series should be fixed at one end, the other being free, a new differentiation must arise; for the two ends being very differently situated, the intermediate ones will also differ accordingly as they are nearer one end or the other. Here there is a cause for the differentiation of united individuals that does not exist in any branched or other symmetrical arrangement than a linear one. Some of the Salpida show such a rudimentary linear aggregation, but their mouths and vents being lateral the individuals are so similarly situated that no differentiation need occur. A little consideration will show us that this is one of those cases in which perfectly transitional forms are not to be expected. A permanent union of individuals in a linear series, such as to necessitate differentiation of function among them, could only be effected by a series of co-ordinated gradations, each of which would have so great an advantage over its predecessor as to necessitate its extinction in the struggle for existence. We cannot expect to find the union without the differentiation, or the differentiation without the complete union; and it will, therefore, be impossible to prove that such was the origin of any group of animals, except by showing that numerous traces of separate individualities occur in their organisation, and cannot be explained by any of the known laws of development or growth in animals not so compounded.

In the structure of the lower Annelids we do find strong indications of such an ancestral fusion of distinct individuals. These animals are composed of segments, not merely superficial, but exhibiting throughout a wonderful identity of form and structure. Each segment has its branchiæ, its enlargement of the alimentary canal, its contractile dilatation of the great blood-vessel, its ganglia, its branches from the nervous and vascular trunks, its organs of reproduction, its locomotive appendages, and, sometimes, even its pair of eyes. Thus every segment is a physiological whole, having all the organs essential to life and multiplication. Again, just as other compound animals increase by gemmation or fission, so do these. The embryo leaves the * Extracted from an Address read at the Anniversary Meeting of the Entomological Society of London on the 22nd January, 1872, by Alfred R. Wallace, F.L.S., F.Z.S., President, &c.

anterior segment. In the Nemertidæ, and some Planaria, spontaneous fission occurs, each part becoming a perfect animal, and in the Tænia this is the usual mode of reproduction. The account given by Professor Owen in his "Comparative Anatomy of Invertebrates" is very suggestive of Mr. Spencer's view. He says:-"On the first appearance of the embryo annelid it usually consists of a single segment, which is chiefly occupied by a large mass of unmetamorphosed germ-cells. And these are not used up, as in higher animals, in developing the tissues and organs of an undivided or individual whole, but, after a comparatively slight growth and change of the primary segment, proceed in the typical orders to form a second segment of somewhat simpler structure, and then repeat such formations in a linear series, perhaps more than a hundred times. So that we may have a seeming individual annelid, consisting of many hundred segments, in which a single segment would give all the characteristic organisation of such individual, except some slight additions or modifications, characterising the first and last of the series." He also tells us that spontaneous fission has now been observed to take place in almost every order of Annulata; and, in many, artificial fission produces wo distinct individuals. In some cases the compound animal consists of very few segments, three only in the genus Chatogaster, the fourth always separating as a zooid, and forming a new animal. In the higher Articulata, the process of gemmation goes on to a considerable extent in the egg, and even afterwards in some cases, but more or less irregularly. Thus the larva of Iulus is hatched with eight segments, and at the first moult it acquires six new ones, which are added between the last and the penultimate.

The gradual fusion of the once distinct individuals into a complete unity, is shown in a very interesting manner as we advance from the lower to the higher forms. In the Annelida, Dr. Carpenter tells us, the spiracles of each segment are separate, and do not communicate internally with those of other segments. In the Myriapoda they partially communicate, while in the Insecta they communicate perfectly by a system of anastomosing vessels. The same thing is indicated by the various positions of the chief spiracles. In Smynthurus among the Podurida there are only two, opening under the side of the head immediately beneath the antennæ. In Solpugidæ (Arachnida) they are situated between the anterior feet; in some spiders they open near the end of the abdomen, in others at its base. The position of the mouth and eyes at the anterior extremity of the body, and the vent at the posterior, are obviously what would arise as soon as any specialisation of function in the series of zooids occurred. It is not, therefore, surprising that we never find these change their position. But for the respiratory and generative organs there is no such necessity for fixity of position, and as they existed originally in every segment, we can well conceive how, as articulate forms become more and more modified, it would sometimes be useful to the compound animal for these organs to become abortive or developed in different parts of the body. We have seen that this is to some extent the case with the former organs, but it occurs to a much greater extent with the latter.

The most generalised form is to be seen in the intestinal worms, each segment of which possesses a complete hermaphrodite reproductive apparatus; so that, in this respect, no less than in their capacity for spontaneous fission, these creatures are really what we should expect the early type of compound animals to be. This, however, is a rare case, but even in the much higher leeches there are testes in no less than nine of the segments, and Dr. Williams discovered a direct passage from the spermatheca to the ovaries, which seems to indicate internal self-fertilisation. It is, however, in the lower Arthropoda that we find the most curious diversities in the position of these organs. In the Glomerida the genital openings in both sexes are situated in the third segment, just behind the insertion of the second pair of limbs. In the Polydesmida the female organs are in the third segment, while those of the male are in the seventh segment. In Iulus the same organs are situated in the fourth and seventh segments respectively. The Chilopoda, on the other hand, have them near the end of the body, as in most insects. In the Acarina the ovaries open on the middle of the abdomen or on the under side of the thorax, either between or behind the last pair of legs. In spiders the seminal orifice is at the base of the abdomen, but the palpi are the intromittent

organs; these are spoon-shaped, and are besides armed with horny processes, hooks, and other appendages, and must be looked upon as true generative organs. In the Astacide the sexual organs of the male are at the base of the first pair of abdominal legs, those of the female at the base of the third pair. Among the true winged-insects there is one remarkable case of abnormal position of these organs, in the dragon flies, which have the seminal vessels in the ninth, while the complex male sexual organs are situated in the second, abdominal segment. It is interesting to note that this curious anomaly occurs in an order which is considered to be of the greatest antiquity and most generalised type among the true insects.

There are many other facts of a similar character to those I have now touched upon, and they all become clearly intelligible on the theory of Mr. Spencer, that the Annulosa are really compound animals, or, as he expresses it, "aggregates of the third order;" while the other great groups of highly organised animals-Mollusca and Vertebrata-are typically simple animals, or "aggregates of the second order," (the cells of which their structures are built up being "aggregates of the first order "). Nothing of a similar character is to be found among the two latter groups. No molluscous or vertebrate animal can be divided transversely so that the separate segments shall be in any degree alike, and contain repetitions of any important organs. The distinct separation of parts in the vertebral column has been acquired, for it is less visible in the lower types than in the higher (the reverse of what obtains among insects), and in the lowest of all is quite absent; while in none is there any corresponding multiplicity or displacement of respiratory, circulatory, or generative organs. The vertebral column corresponds rather to the segmented shell of the Chiton, and has no more relation than it to the essential plan of the more important vital organs. Neither does any mollusk or vertebrate undergo spontaneous fission, nor that complete and progressive segmentation in the process of development which is characteristic of all Annulosa; nor do they ever exhibit the phenomena of parthenogenesis or alternation of generations, the essential feature of both which is, that numerous individuals are produced from a single fertilised ovum, by a process analogous to (or perhaps identical with) ordinary gemmation, and both which phenomena sometimes occur even among the higher insects.

In concluding this short sketch of a remarkable theory, I would observe, that if it is a true one it at once invests the objects of our study with a new and exceptional interest; because they are the most highly developed portion of a group of animals which will, in that case, differ fundamentally in their plan of structure from all other highly organised forms of life. In the study of the habits, instincts, and whole economy of insects, we shall have to keep ever in view the conception of a number of individualities fused into one, yet perhaps retaining some separateness of mental action, a conception which may throw light on many an obscure problem, and which will perhaps materially influence our ideas as to the nature of life itself. We must remember also, that if the insect is really a compound animal, then the only true homology that can exist between it and a vertebrate, or a mollusk, will be one between a single segment and an entire animal, and the search after any other will be so much lost time. Especially must the acceptance of this theory have an important bearing on all embryological and genetical studies; and if the facts and arguments adduced by its learned and philosophical author do make out even a prima facie case in its favour, it must deserve the careful and unbiassed consideration of all who endeavour to solve the problem of the Origin of Insects.

THE AUSTRALIAN ECLIPSE EXPEDITION

WE have already announced that no scientific results are to be expected from the Australian Eclipse Expedition, owing to the unpropitious state of the weather. The following particulars are obtained from the Melbourne Argus:—

"The five days intervening between the arrival at No. VI. Island and the eclipse were employed by the astronomical party in erecting and testing the instruments. Tents had to be put up, brick foundations and pedestals built, and distances determined. There was plenty of hard work, and the time at the disposal of the astronomers was found to be none too much. Nor were those who had to sleep on shore with the instruments to be envied. Possession of the island was hotly disputed by

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legions of rats, who behaved in the most impudent manner. They boldly eyed the operations in the daytime, winking wickedly from behind the tufts of grass. Every night they held a corroboree in the tents, coursing over the instruments and the forms of the wearied sleepers, gnawing hats and any baggage which promised a toothsome morsel; and in some instances they had the audacity to bite the men who attempted to brush them away. The passengers filled up the interval by visits to the mainland, and one or two of the neighbouring reefs and islets. On Thursday, December 8, Mr. Moore formed a party and went to Cape Sidmouth, the boat carrying provisions for three or four days. A native on the beach seemed much alarmed at their approach. When they landed he ran off at full speed and was not seen again. Only two other blackfellows showed themselves, though the tracks and camp fires proved that there were many in the neighbourhood. These blacks were known to be hostile, and it was necessary to take precautions to guard against a surprise. The master of the schooner Challenge, from Sydney, bound for Cape York, passed with his vessel a few yards astern of the Governor Blackall that morning. On hearing that a party had set out with the intention of landing at Cape Sidmouth, he expressed the consoling opinion that if they entered the bush they would never come out of it again. But no such disaster befel.

"On the hills, which rose abruptly a few hundred yards from the beach, were well-defined quartz reefs, and the neighbourhood presented all the appearance of auriferous country. A few miles from Cape Sidmouth was found an enormous heap of the bones of the dugong, the strange mammal which inhabits these seas. There were nearly two tons of bones, piled up in fantastic array, with all the skulls on top. At every turn were ant-hills, rising in solid cones from 6 ft. to 12 ft. high, and almost as hard as granite. Some of them had fine pinnacles, and these airy minarets, clustered together in graceful shapes, had a very pleasing effect. The numerous screw pines were also an agreeable feature in the landscape. The mountains, eight or ten miles inland, were well wooded, with occasional abrupt squares of grassed land.

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Mr. Moore prosecuted his botanical researches on the mainland during two days. Those who understand botany may be interested to learn from his account that the high ground at the cape is sparsely covered with stunted growths and trees, chiefly Eucalypti and Grevillea chrysantha. Advancing into the interior, broad-leaved acacias and arborescent species of Hakea and Melaleuca principally characterise the open forest country. There are belts of thick jungle scrub of no great width, in which a very slender and graceful palm, which is believed to be new, occurs in great abundance. A species of Nepenthes, or pitcher plant, is also found in great profusion. Araliaceous trees are numerous. Ferns are scarce, but in the open forest the ground is thickly covered with Schizaa dichotoma. A very remarkable plant was found as an undergrowth in this, having large white bracts and bright green foliage. It is supposed to be a species of Mussanda. Toward the north of the cape is a long, low, flat country, chiefly covered with mangrove. The sandy patches contain a variety of undershrubs and climbers, with a tree here and there. silk-cotton plant (Cochlospermum gossypium) also varies the scene with its delicate flower. Among these shrubs a very interesting plant-a species of Eugenia-was found. It bears a fruit about the size and colour of a cherry, having a pleasant sub-acid flavour. This fruit was largely eaten by the party, and the tree which bears it is supposed to be well worthy of cultivation. The vegetation is otherwise principally characterised by a species of Busbeckia, Elæodendron, Hibiscus, Bauhinia, and a species of Banksia. After leaving the mainland the party visited No. VII. Island of the Claremont group, where Mr. Brazier added an Auricula and a Bulimus to his previous collection of shells, which included specimens of the genera Diplommatina, Pupa, Helicarion, Helix, Truncatella, Pythia, and Cassidula. Had the expedition selected a portion of the mainland for the observing point, there would have been some interesting and extensive explorations in the interior. The party were fully equipped with arms and ammunition, some supplied by the Government and some privately owned, but with the ship nine miles off, and the limited time at our disposal, much exploration was impracticable. In any case, there was no anchorage for the vessel within two miles of the shore, and that was one of the reasons why the island was preferred for the observatory.

"On Thursday afternoon, some of the excursionists went in the captain's boat to look for shells on a small sandbank which had come into view, and landed on an island considerably smaller

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