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the ancient Britons. Slaves were sacrificed at their master's graves, and wives, there can be no doubt were sacrified and buried with their husbands, to accompany them in the invisible world upon which they were entering. It is reasonable, therefore, to infer that infants were occasionally sacrificed on the death of their mothers, in the belief that they would thus partake of her care in the strange land to which, by death, she was removed. Whether from sacrifice, or from natural causes, the mother and her infant may have died together, it is only reasonable to infer from the situation in which these “incense cups" are found, (either placed on the top of a heap of burnt bones or inside the sepulchral urn contaiving them) and from their usually containing small calcined bones, that they were receptacles for the ashes of the infant, to be buried along with those of its mother.
(To be continued.)
THE STRUCTURE OF THE ANNELIDS, WITH A
CRITICISM ON QUATREFAGES.
By EDOUARD CLAPAREDE.
M. CLAPAREDE has kindly sent us a pampblet on the above subject.* It is taken from the introduction to a work on the Annelids of the Gulf of Naples, now in the press under the auspices of the Societé de Physique et d'Histoire Naturelle de Genève. M. Claparède spent six months at Naples during the winter of 1866-7, and found the locality extremely favourable for the study of Annelids. He observes that his remarks were facilitated by the recent publication of two works, one by Al. Ehlers, and the other by M. Quatrefages; although, in addition to other defects, he found the book of the latter full of typographical errors to an extent “passing imagination,” and likewise of false citations. Only one part of M. Ehler's work has appeared. It relates to certain Nereids of the Adriatic, and does not correspond with the generality of its title-a “ Treatise on the Annelids.” What M. Ehler has done, M. Claparède pronounces to be a “model of exactitude." “L'Histoire Naturelles des Annelés,” of M. Quatrefages, is a treatise on the Polychatian Annelids, in which the author endeavours to fulfil two purposes-a natural classification,
* “De la Structure des Annélides, note comprenant un examen critique des travaux les plus recents sur cette classe de vers. Genève, Ramboz."
is-deseri instances a be read
based upon anatomy, and an enumeration of synonyms. In referring to the writings of others, M. Claparède states that M. Quatrefages has “often consulted plates without taking the trouble to read the corresponding text.” One instance of this occurs in a mis-description which he gives of Claparède's genus Pygaspio, and other instances are given. While admitting that M. Quatrefages's work may be read with advantage, M. Claparède cannot admit that it represents the present state of science, as regards the anatomy and physiology of worms. “Unfortunately, notwithstanding his numerous and profound researches, the author of the ‘Histoire Naturelle des Annelés” has too often forgotten that he had predecessors, and that contemporaries were exploring the same ground with an ardour equal to his own.” The “personality of M. Quatrefages' the ridiculous egotism in fact, so noticeable in his works-"is always foremost, even in the narration of facts known twenty or thirty years before his own scientific début. ... How many errors would have been avoided if the author had conscientiously studied the works of Rathke, Della Chiaje, Grube, and others; if he had taken into account the studies of histologists, such as Kölliker, Leydig, etc., he would not then, as he has sometimes done-in the structure of the branchiæ, for example-have made science retrograde to the epoch of Pallas.” “Why did M. Quatrefages, who is so well acquainted with Annelids, describe genera and species from specimens preserved in alcohol in the Paris Museum ? He must know the uselessness of such a course, and that Annelids can only be properly studied at the sea-side with the help of living specimens. To describe as he has done, alcoholic varieties, is to embarrass science with a caput mortuum, which it will take years to get rid of.”
“Regions of the Body and Appendages. After much discussion concerning the value of the external portions of the bodies of Annelids, most recent authors have adopted the nomenclature of M. Grube, who gives the name of buccal segment to the segment carrying the mouth, and that of cephalic lobe (Præstomium, Haxley) to all that is in advance of it. ..... M. Quatrefages, taking up opinions previously advanced by Rathke, considers the cephalic lobe and the buccal segment as together forming the head, but he does not adhere strongly to this view, as he most often gives the name head to the cephalic segment only.”
“He has tried to introduce a simplification in the nomenclature of the appendages of the cephalic region, by giving the name of antennce to all the appendages springing from the cephalic lobe, that of tentacles to those of the buccal segment, and that of tentacular cirrhi to those of the first feet, when they exhibit in a marked manner characters which distinguish them from their homologues belonging to the hinder feet.”
“ This nomenclature, which at first appears a happy one, has many inconveniences, and is frequently inapplicable to particular species. In the first place, the appendages of the cephalic lobe are sometimes quite different from each other in formation, as well as in structure, on which account most authors have given them different names. What a difference, for example, there is between the palpi (lateral antenne, And. and Ed. Qtfg.) and the frontal antennæ of the Lycoridians. The first are fleshy, many-jointed, partially retractile, filled by the prolongation of the largest nerve in the body , the second are filiform, simple, non-retractile, poor in nerves. An equal distance separates the palpi (Kimberg, and all recent authors) and the true antennæ of the Aphroditians. ... A second inconvenience of M. Quatrefages's nomenclature is its inapplicability in all the cases in which the anterior segments are very condensed, and in which it is not possible to determine to which segment a pair of appendages belong.... The learned Academician, enamoured of his theory, suppresses by a stroke of his pen the buccal segment of the major part of the Sigalionides—at least, he ascribes to them only “an indistinct buccal ring, deprived of appendages.” Nothing is, however, more distinct than the buccal segment of these worms, only it carries a pair of feet with their bristles, and cannot be a buccal segment according to the theory of M. Quatrefages. Unfortunately, the author does not know that all the Polynoes have bristles on the segment which he regards as buccal, and that it would be necessary to imagine for them a distinct buccal segment without appendages."
“M. Quatrefages, however, gives a rule difficult of application, but still a rule for the determination of segments and their appendages. The cephalic lobe and the antennæ, he says, receive their nerves from the cerebral ganglion; the buccal segment and its tentacles, from the @sophagal connections ; the tentacular cirri, from the ventral ganglionic chain. This proposition cannot be maintained in the face of modern embryology. Schaum had already asserted that, throughout the articulata, each segment is characterized by the possession of a ganglion, and from this principle he denies that the head of the Anthropoda is formed of many united segments. This doctrine was immediately refuted. In fact, the nervous system differentiates itself relatively very late among the Articulata. On the contrary, the appearance of segments-protozonites, as they are called—is, in many cases, the result of one of the first modifications of the blastoderm. These primitive segments unite in groups, and frequently solder themselves together long before the differentiation of the nervous system ; and when this system is developed, the number of ganglions is not necessarily identical with that of the primitive segments. Amongst Annelids, in particular, the formation of a nervous system sometimes follows pretty closely that of the segmentsamong the embryos of the Capitelles, for example--but it is usually later. I do not dispute that among many Annelids the birth and distribution of nerves conform to the rule of M. Quatrefages. But we see that in certain cases it is not the buccal segment only, but also some of the following segments, which receive their nerves from the æsophagal connexions. It is so among certain Aphroditians, Hesionians, etc. ....I employ the name Antenna for all the appendages of the cephalic lobe; but when two of these appendages spring from the inferior portion of the lobe, and present special anatomical and physiological characters. I, in common with the majority of authors, call them palpi. The modified cirri of the buccal and following segments are called in this memoir tentacular cirri."
“Without wishing to dilate on the conformation of the feet of the Annelids, I would indicate the relation of the bristles to the tissues environing them. Some authors consider them as enclosed in a pocket which is merely an invagination of the teguments, and others think they are engendered in an internal follicle, and only arrive in a secondary way at the surface. This second opinion is correct. Among the Hesions and others, for instance, the whole bunch of bristles come in a compact form out of a single pedal opening, but in other cases each bristle has its own special aperture. This is especially the case with the flabelliform tufts. The issuing pore of each bristle is not preformed. The bristle makes its own perforation, which is easy when the tissues are soft, but it is not so when the worm is protected by a resisting cuticle, and when the bristle, armed with hooks in different directions, might entangle themselves in the tissues, and produce serious rents. In these cases the extremity of each bristle is surmounted with a small provisional apparatus, terminating in a very keen blade, destined to cleave a free way for the bristle, and to avoid tearing. The form of this cutter varies much with that of the bristle, and especially of the hooks, whose passage must take place without tension of the adjacent parts.”
Teguments and Muscular Apparatus.-" The teguments are composed of two layers-one internal and cellular (Corium, Rathke, derme, Quatrefages), corresponding to the sub-cuticular or chitinogenous layer of other Articulata ; the other extracellular, the cuticle (epiderme, Rathke, Qtrfg.) sometimes very delicate, sometimes composed of a thick layer of chitin. Up
to the present the teguments have only been carefully studied by Külliker, to whom we owe many excellent papers on the histology of the Annelids, which are unfortunately quite unknown to the author of the “ Histoire Naturelle des Andelés.”
“The superficial layer deserves the name which Kölliker has given it. In a histogenetic point of view it belongs entirely to the category of cuticular formations. The subcuticular layer (hypoderm, Weissman) which secretes it—often called with Kölliker epithelium-in most cases does not enable us to recognize the boundaries of its constituent cells. The nuclei appear sown with great regularity in a continuous granular layer, as M. Bauer has seen in certain Arthropoda. Whenever the cuticle attains a certain thickness it is seen to be ornamented with two systems of striæ at right angles to each other, or more frequently at about 70°, as noticed by M. Kölliker. The tubular pores (porenkanale of the Germans), wherever they exist, are disposed in lines conforming with the striæ. M. Kölliker has been struck with the difference of these pores from each other. Often, he says, they correspond only with a subjacent cell, and he asks if these openings are really homologous with the tubular pores of the Arthopoda, and do not rather resemble the openings of cutaneous glands discovered by Leydig in the Piscicoles, or the hairs of insects and crustaceans. To these questions I can reply in a positive manner that both sorts of pores exist amongst the Annelids. Those which serve for the outpouring of certain secretions appear to exist in all species. In large species they are sometimes of considerable diameter, but usually very limited. Sometimes they are found united in groups. The canalicular pores are much smaller, much nearer together, and have no resemblance to glands. They are only found in species which have a thick skin, and not in all of these. . i . The subcuticular layer—the derme of M. Quatrefages-appears always to contain glandular follicles, and that in all parts, even in the cirri and antennæ. These follicles empty themselves externally by means of the glandular pores. Some only secrete a thick liquid, others engender bundles of little rods (batonnets), and these I have named bacilliparous follicles; others only secrete granules.”
M. Claparède explains that the bibliography of these bacillary corpuscles is very rich, and he wonders that it has altogether escaped the notice of M. Quatrefages. “ Certain families,” he says, “ have their teguments literally covered with bacciliparous follicles, even in the cirri and the antennæ. This is especially the case with all the Aricians and Spiodians, and a great part of the Chætopterians. Their abundance is likewise remarkable in a crowd of Phyllodocians, and in certain Hesionians. Among the latter especially, their grouping and