Imágenes de páginas

usually very distinct. Sars considers it most likely that these creatures derive their nutriment from the juices of the fuci, etc., amongst which they are usually found, for though the structure of the suctorial apparatus is very much akin to that of the parasitic Entomostraca, none of the Ostracoda have ever been found as parasites. It is, indeed, impossible to regard the members of this genus as parasitic, but neither do I think it likely that the poison gland and urticating setæ, which are with them very largely developed, can be meant to assist the creatures to prey upon vegetable food. It seems more likely that they serve an office similar to the. urticating filaments of the Actiniæ in paralyzing the more minute animal organisms on which their owners probably subsist.

The genus is an especially littoral one, almost all its members being met with in tidal pools, though some of them range also into and beyond the Laminarian zone. The shell is usually very thin, pellucid, and variously marked with shades of olive, deep purple, or black.

Family—CYPRIDINIDÆ, Baird.

PHILOMEDES, Lilljeborg. - Upper antenna six-jointed, scarcely attenuated at the apex, antepenultimate joint bearing a stout seta, which is set with numerous long auditory cilia ; last joint short, and bearing two setæ, which are much longer than the antenna itself. Secondary branch of lower antenna, three-jointed, geniculated, last joint turned upwards. First pair of jaws slender, palp bearing simply a small trisetose lobe; second pair having neither a mandibuliform appendage, nor . clawed spines. Animal swimming with long jerks.

P. interpuncta (Baird).—This is the most abundant of the British Cypridinidæ, being sometimes taken in considerable numbers by the towing-net, and occasionally in tidal pools. It ranges, in our islands, from Guernsey to Shetland. The shell is thinner than in others of the family, and often finely reticulated on the surface. Identical with P. longicornis, Lilljeborg.

CYLINDROLEBERIS, nov. gen.-Upper antennæ of the male (Fig. 11) bearing at the apex two excessively long, annulated setæ, four shorter setæ and a short curved claw ; penultimate joint bearing at its apex a stout, densely ciliated auditory seta ; upper antenna of the female (Fig 12) terminated by a stout curved claw, and six or seven subequal plumose setæ, which do not exceed in length that of the last four joints ; penultimate joint bearing a stout seta or process, from the extremity of which spring six similar setæ. Second joint of the natatory

branch of the lower antenna in the male elongated; in the female scarcely longer than the succeeding joints ; secondary branch in the male (Fig. 13) robust, subchelate, terminal joint slender, curved upwards; in the female simple, triarticulate, last joint setiform. Antepenultimate joint of the mandibular foot shorter than the following joint, bearing three long subequal curved setæ, two of which are plumose; last joint very short, armed with a curved claw and several setæ. First maxilla, consisting of a broad subquadrate or crescentic lamina, densely clothed on its distal side with long bristles; second pair.swollen at the base, suddenly narrowed toward the apex, interruptedly setose; third narrow, uniformly setose. Oviferous foot terminating in two equal dentate lips (Fig. 14), and bearing about six pairs of spinous setæ. Shell elongated, fusiform, or subcylindrical, smooth ; beak rounded, and not at all produced ; notch narrow. Animal swimming freely.

C. Mariæ (Baird), teres (Norman).—Mr. Robertson takes these species in the Frith of Clyde (though never very abundantly) by means of the tow-net, during the night. It would seem, indeed, that these animals do not come to the surface except after sunset. This observation suggests that possibly in fresh-water lakes something might be done by naturalists during the “wee sma' hours ayont the twal.”

BradyCINETUS, G. O. Sars.-Terminal setæ of the upper antenna short and subequal. Secondary branch of the lower antenna in the female (Fig. 15) small and biarticulate, the last joint obtuse, and bearing at the apex a flexuous seta ; in the male larger, three-jointed, the last joint long and membranaceous, terminating in two short setæ. Mandibular feet (Fig. 16) armed with a bifurcate process, in front of which are three toothed spines. Second pair of jaws having a strong mandibuliform appendage, composed of two robust tooth-like processes. Eyes small, and of pale colour. Animal mostly crawling slowly amongst mud. Shell much thicker and stronger than in the preceding genera, produced in front into a large beak, with a deep subjacent notch.

B. Brenda (Baird), MacAndrei (Baird).

BRADEchot and subertig. 15) small an fexuous


CONCHOECIA, G. 0. Sars. This is the only genus of the family, and is sufficiently described previously (pp. 115, 116).

One speciinen only has been seen in Britain, and is probably referable to C. obtusata, G. 0. Sars. It was found by the Rev. A. M. Norman, in sand dredged off Shetland.

Family–POLYCOPIDE. POLYCOPE, G. 0. Sars. The principal characters of this genus are those of the family to which it belongs, and of which it is the only member.

P. orbicularis, Sars.; dentata, Brady. — The first-named species is probably not very uncommon, but owing to its small size-'th of an inch-is very likely to be often overlooked. It has occurred in Connemara, Shetland, and the West of Scotland. The shell is almost spherical, and often beautifully punctate and marked out into polygonal areolæ. Of the second species only one example has yet been found; this occurred to Mr. Norman in the same gathering as that which yielded the Conchoecia. According to the investigations of G. O. Sars, these animals are wonderfully active in the water, having no less than ten limbs adapted for swimming.

Family—CYTHERELLIDÆ. CYTHERELLA, Bosquet.—The anatomical structure has been noticed in the description of the family. The shell is very thick and dense in structure, the lateral outline mostly elliptical, and the hinge formed by a simple grooving of the edge of one valve into which the margin of the opposite valve is received. The “lucid” spots* are arranged in a curved pinnate series.

C. Scotica, Brady ; lævis, Brady.--Both species are very rare, and hitherto have been found only amongst the Hebrides. The former is closely allied to a Norwegian species described by Sars-C. abyssorum. Several fossil species have been described by various authors; the great thickness and durability of the shell may perhaps account for this.

d” spod Brady; Run found only amal species d

C. Scotinats * are arranged opposite valve is me of one valve

Brady, Tved pinnateceived. valve

Sarsher is clos have been

EXPLANATION OF PLATE I. Fig. 1.-Illustrating the anatomy of the female of the genus Cypris : a, eye; b, upper antenna ; c, lower antenna; d, mandible proper; e, its branchial appendage; f, its palp; g, first maxilla ; h, its branchial plate; i, second maxilla, with branchial appendage; j, first foot; k, second foot; 1, abdomen; m, post-abdominal ramus; n, alimentary canal ; 0, ovary.

Fig. 2 illustrates the anatomy of the genus Cythere : the letters used refer to the same organs as in Cypris, except those following: r, s, t, first, second, and third feet; v, poison gland, communicating with the urticating seta (flagellum) of the lower antenna.

* These, though existing in all Ostracoda, have not, for the sake of brevity, been previously noticed, though they sometimes afford good generic characters. They are, in fact, thin, depressed portions of the shell which afford attachment to the muscular bands by which the animal is attached, and by which it is enabled to close the valves firmly.


Fig. 3.-Rudimentary post-abdominal ramus of Cypridopsis.
Fig. 4.—“Glandula mucosa” of male Candona candida.
Fig. 5.-Second foot of Pontocypris mytiloides.

6.- Post-abdominal ramus of P. trigonella.
Fig. 7.-Upper antenna of Limnocythere inopinata.
Fig. 8.-Upper antenna of Cytherilea papillosa.

Fig. 9.-Abdomen and post-abdominal setæ of Cytheridea torosa.

EXPLANATION OF PLATE II. Fig. 10.-Illustrating the anatomy of Bradycinetus (adapted from Lilljeborg): the letters are used with the same references as above, except the following: 1, secondary branch of lower antenna; 8, mandibular appendages of branchial plate of second maxilla.

Fig. 11.-Upper antenna of male Cylindroleberis Mariæ.
Fig. 12.-Upper antenna of female Cylindroleberis Mario.

Fig. 13.-Secondary branch of lower antenna of male Cylindroleberis Mariæ.

Fig. 14. — Termination of oviferous foot of Cylindroleberis Mariæ.

Fig. 15.—Secondary branch of lower antenna of female Bradycinetus VacAndrei.

Fig. 16.—Mandibular foot of Bradycinetus Brenda.

Fig. 17.-Termination of oviferous foot of Philomedes interpuncta.

Fig. 18.—Post-abdomen of Philomedes interpuncta, seen from below.



Captain, 10th Regimert.

The morning of April 6th, 1867, looked rather more promising than usual.* The sun peeped out at intervals from the light cumuloid clouds that screened the eastern heavens; and even the white peaks of the snowy range were faintly visible when we started from our residence on the west side of Jella Pahar, with the intention of walking to the summit of the great mountain called Sinchul, distant, perhaps, some six or eight miles from Darjeeling, and 8600 feet above the level of the sea. This noble hill-one of the loftiest in British Sikkimis a grand and striking object from any point of view; and its numerous spurs and ramifications furnish nearly all the greater summits in the neighbourhood, upon which are built the stations of Jella Pahar and Darjeeling, and the settlements of Leebong, Tukvar, Dooteriah, Senadah, and Hope Town.

Having crossed the ridge of Jella Pahar, we found ourselves in the main road, leading, with a gentle slope, from a dip in the mountain called the “saddle” to the Sinchul barracks, which are situated fully six hundred feet higher up. But before we had gone very far, great piles of mist began to rise from the khuds and valleys below, ever and anon shutting out the view of all objects beyond a hundred yards, and threatening, ere long, to shroud the entire prospect, for the remainder of the day, in a dense mantle of heavy cloud.

The road winds slowly upwards, passing through the mutilated remains of glorious forests, that once overspread this mountain-side from base to summit, but which now, alas, in the vicinity of the highway and the military station, are very nearly obliterated from the soil that fed and nourished them, for, perhaps, thousands of years before the axe or the clearing-fire brought destruction amidst some of the fairest scenes on earth. But, even here, all the trees are not yet gone, and aged giants of towering height and huge proportions, gnarled, moss-covered, green with orchids, and festooned with climbers, still stand, among the unsightly stumps of their departed brethren, perfect marvels of magnitude, grandeur, and solemn majesty.

The walk to Sinchul is, to me, a somewhat melancholy one,

* The weather at Darjeeling and its vicinity has, this year, been almost continually cloudy since the end of March, as, possibly, before that time also.

« AnteriorContinuar »