PLATE XVI. Fig. 11. Ph. viridis, of the natural size. 12. The head and anterior segments magnified. 13. The head and proboscis extruded. 14. The middle segments seen from below. 15. The caudal extremity. 5. Ph. ellipsis, body marked transversely with regular dark fasciæ at the sutures; segments alike and equal; head semioval, rounded in front; posterior tentacular cirri elongated; eyes two; foliaceous cirrus elliptical. Length 23"; breadth "". Nereis ellipsis, Dalyell, Pow. Creat. ii. 152. pl. 20. f. 7–10. Hab. Shores of Scotland: rare. Obs. "Colour greenish to the eye. The microscope discovers two double dark belts crossing the back, on a greenish-yellow broader predominant line."-Dalyell. 6. Ph. Griffithsii, straw-colour, with two interrupted brown fascia across each segment; segments alike and equal; head semielliptical, rounded in front; tentacular cirri longer than the diameter of the body; dorsal cirrus lanceolate, the ventral a roundish papilla; eyes two. Length 8-18"". Hab. The littoral region. Obs. Body slightly attenuated at the head, and more so towards the tail. Oneths in length had 100 segments. The bands across the segments are darker at the middle and edges, so as almost to become spots. Eyes two, small. There are five antennæ, and four pairs of tentacular cirri, the first pair attached to the first segment, the second and third pairs to the second, and the fourth pair to the third segment. The dorsal cirrus is much larger than the ventral, which is roundish. The setigerous tubercle and setæ are inconspicuous from the back; and there is a single spine to each foot.— F. D. Dyster. The specimens which I refer to this beautiful species have had their markings discharged by the spirits in which they are preserved; and now resemble in colour, as in form, the Geophilus maritimus. A specimen 14" long had about 130 segments. The branchial cirrus is very accurately lanceolate-acute, and beautifully veined like a leaf, with a midrib reaching the point. The proboscis is one-third the length of the body, papillose. (a) Torbay, J. R. Griffiths. 7. Ph. cordifolia, green; segments alike and equal; head semielliptical; tentacular cirri in four pairs, all attached to the first segment; dorsal cirrus heart-shaped, pedicellate; the inferior conical. Phyllodoce cordifolia, F. D. Dyster in lit. Hab. On oyster-beds in 5 fathoms, Dyster. Obs. Head small, conical, with two eyes near the posterior line. There are about 50 to 60 segments. Dorsal cirrus expanded into a cordate lamina indented at the base. Ventral cirrus short and conical. Bristles slender, with the acicular terminal piece serrulated along the edge, as seems to be the case in all the species. Very active, swimming with vigorous serpentine movements.-F. D. Dyster. ** The body proportionably short, and consisting of fewer segments; all the cirri filiform and elongate. Hesionea (p. 175). 16. PSAMATHE*. Castalia, Savigny, Syst. Annel. 1820, 46. Oersted, Annul. Dan. Consp. 23. Grube, Fam. Annel. 58: not Lamk. Psamathe, Johnston in Loud. Mag. Nat. Hist. ix. 14 (1836), and in Halimede, Rathke in Nov. Act. Curios. Cæsar. xx. 167 (1843). Ray Char. Body scolopendriform; head small, with two small antennæ and two palpi alike in form; eyes four, in pairs: proboscis short and cylindrical, furnished with a pair of slender, weak, lightcoloured jaws, and encircled on the orifice with papillæ post-occipital segment similar to the others: tentacular cirri four pairs, unequal, elongate: "feet with two branches, the superior very minute, the inferior large, three-lobed, a single spine in the superior branch, three in the inferior; the bristles in the superior capillary and very slender; in the inferior much stronger and falcate."Oersted. This genus, which I have named Psamathe, in honour of the daughter of Nereus and Doris, will take rank, as it appears to me, between Syllis and Hesione. It differs from the first in the number and structure of the antennæ, in the form of the head, and in the arrangement of the eyes; and from the latter in the form of the body (which is, in this family, an important character) and in the structure of the proboscis. In Hesione this is very long, and destitute of oral tentacula. * A Nereid: "And Psamathè for her brode snowy brests."-SPENSER. Sars writes the name Psammate (Adriat. Havs Fauna, p. 9). According to Oersted, the genus is the same as the Castalia of Savigny, instituted in 1817. It is undoubtedly synonymous with the Halimede of Rathke. 1. P. punctata, papillæ on the orifice of the proboscis numerous and close; dorsal cirrus filiform, longer than the diameter of the body, distantly jointed. Length 1". Plate XIV. fig. 4. Nereis punctata, Müll. Zool. Dan. Prod. no. 2633; Zool. Dan. ii. 28. Nereis rosea, Fabric. Faun. Grænl. 301. Baster. in Phil. Trans. Psamathe fusca, Johnston in Loud. Mag. Nat. Hist. ix. 15. f. 1, and Castalia punctata, Oersted, Annul. Dan. Consp. 24. f. 15, 63, 64, 65 & 69. Nereis punctata villosa, Dalyell, Pow. Creat. ii. 158. pl. 21. f. 11-13. Hab. The littoral region. Desc. Worm scolopendriform, about an inch in length, slightly narrowed in front, tapered towards the tail, of a purplish-pink, yellowish-brown or fuscous colour, and, in the paler specimens, a series of obscure spots may be observed down each side above the feet. Head (No. XXXV. fig. 6) small, square, entire in front. a. Pramathe punctata, considerably magnified. b. The head, with the proboscis protruded, more highly magnified. d. A bristle. e. A spine. Eyes four, very distinct, occipital, placed in pairs. Antennæ four, short, biarticulate, frontal, the superior pair thicker and shorter than the inferior. Mouth furnished with a thick cylindrical proboscis, whose aperture is encircled with a close fringe of papillary tentacula. Tentacular cirri four on each side, the inferior pairs shortest, fili form, jointed, and issuing from a bulged base. Rings numerous, the anterior shorter and smaller than the others, which are nearly of the same length and breadth. Feet (fig. c) much developed and prominent, all alike, conic, the apex emarginate, or divided into two obtuse lobes, between which the bristles are protruded. Superior cirrus elongate, filiform, white, jointed like a Conferva, scarcely moniliform, and arising from a swollen basal joint; ventral cirrus short, extended or not beyond the apex of the foot, not jointed. Bristles (fig. d) all compound, colourless, strong, the point fixed on the shaft like the bill to the handle of a hedge-knife; they are collected into two small but unequal fascicles, having a rather small spine (fig. e) in the middle of each. Anal segment truncate, and terminated with two long styles similar to the tentacular cirri. This little worm is occasionally met with in Berwick Bay, lurking amid the roots of Confervæ, corallines, and sponges; or under small stones in wet sandy soil. It advances through the water with considerable velocity and in a wriggling manner, pushing out and alternately withdrawing the bristles of its feet, and moving its long cirri in every direction. When the creature is first taken and active, the cirri have a somewhat moniliform appearance under the microscope, but as its energy declines this appearance becomes fainter; they then appear jointed like a common Conferva; and, after death, even these joints fade away, and the whole organ assumes a homogeneous structure. When mature, I find that this worm attains the length of about 1 inch. If at rest, and in security, the colour of the back is a dirty green, but there is a narrow band of a purplish-pink colour on each side over the bases of the feet. Now let the worm be alarmed and put in motion, and this purplish colour spreads instantly over the whole body, rendering the worm very conspicuous. This phænomenon I noticed particularly in three fine specimens procured in April*. To observe them more at leisure, I put them into a saucer of salt water with some sand, and allowed them to remain over-night. In the morning nothing was to be seen of one excepting a portion of the anterior extremity. Unsuspicious of the truth, the two others were not separated, and in about six hours afterwards one only was left : he had, imitative of him who mars great Nature's plan, eaten his neighbour up entirely, the neighbour being quite equal to himself in size and strength. I hastened to preserve the cannibal; but when immersed in the spirits, he wriggled until he threw away nearly all his cirri, and then he separated himself into several mangled portions so as to render the body useless for even a coroner's inquest. Obs. Oersted correctly says that I had overlooked the jaws on account of their minuteness and pellucidity, but they could not escape the observation of my friend Mr. Dyster, whose figure of them corresponds exactly with Oersted's description. The bristles are in two small and unequal fascicles, with a small spine in the * Sir J. G. Dalyell says,-"Colour of the finest specimens scarlet; some are yellowish; but the colour is much dependent on the food. It feeds voraciously on mussel, darting out its proboscis, and absorbing a great quantity. The colour changes with the quality of the food." middle of each; and the terminal piece of the bristle is elongate and falciform (seta spinosa, Oersted), serrulated along one edge, and terminated with a minute claw. (a) Holy Island, Dr. Johnston. PLATE XIV. Fig. 4. Ps. punctata, magnified. The line expresses the length of the specimen from which the drawing was made. The Halimede venusta of Rathke differs in having apparently fewer tentacula on the oral orifice. The view he gives is a front one; whereas our figure is taken from a proboscis compressed between plates of glass, by which means the tentacula of both halves of the circle are at once brought into view, and appear crowded. Fam. VII. GLYCERACEÆ*. GLYCERAEE, Oersted, Annul. Dan. Consp. 32. Char. Body vermiform, nearly cylindrical, tapered towards both ends, with numerous segments divided by plain sutures: head small and segment-like, produced into a conical annulated snout with four small antennæ on the apex: no eyes nor tentacular cirri: mouth inferior, with a thick clavate proboscis, emaxillary or usually armed with four hooked jaws, and sometimes also with a series of denticles inserted in the inferior half: post-occipital segment footed like the other segments: feet small, lobulated, with or without branchial simple lobe-like appendages; biramous, the rami partially coalescent: bristles in two fascicles, each with a spine; the bristles simple and compound, the terminal piece dovetailed into the shaft and acicular. Obs. In all the Nereides which we have hitherto described, the head is to be readily distinguished by its enlarged form and its dissimilarity from the first segment; but in the Glycera there is no marked line of separation between these parts. The head has the appearance of a small pointed horn, and is indeed so like the anterior end of the Earth-worm, that we cannot but perceive, in this sameness of character, a certain approximation to a junction between the families to which the Glycera and Earth-worm respectively belong. Yet though this is unquestionable, still the Glycera is not the nearest connecting link, for there are other Annelides errantes which partake more of the habits and character of the Terricola. 17. GLYCERA. Glycera, Savign. Syst. Annel. 36. Lam. Anim. s. Vert. v. 314. Aud. & M.-Edw. Litt. de la France, ii. 241. Blainv. Dict. des Sc. nat. lvii. 484. Williams in Rep. Brit. Assoc. 1851, 198, 214 (not R. Brown). Char. Proboscis with four black spinous and hooked jaws placed * From yλvкepòs, suavis, pleasant to look upon. |