OCR Text |
Show 266 MR. P. S. ABRAHAM ON THE [Mar. 6, small, thin, subcrenulate, waved, and transversely striated. Rhinophores apparently short, clavate, laminate and rounded above, retractile within small cavities approximated and far forward in position. Branchiae 8, small, stout, imperfectly tripinnate, retractile in the deep cavity, the margin of which is irregularly denticulate and completely contractile. Foot short, broad, truncate in front, not extended behind : above the marginal opening for the proboscis are two small tentacular lobes. Colour of the spirit specimen transparent greyish white, with the branchiae and the margins of the mouth and of the foot rather darker and more opaque. Length (in spirit) 21 millims., breadth 14, height 11. Hab. St. Vincent (West Indies). DORIDOPSIS MAMMOSA, sp. nov. (Plate XXIX. figs. 20, 21.) Body broadly elliptic, convex on the back, very soft and gelatinous. Mantle extended all round, semitransparent, and wavy at the border. Along each side of the back is a row of 3 large, conical, elongated, soft processes, now and then bearing a few tubercles near the base, and sometimes rather rugose at the apex ; two similar processes are situate between the rhinophores; and smaller soft tubercles are scattered rather irregularly upon the sides and upon the back. Rhinophores clavate and slender, the upper portion diagonally laminated and with rounded tips ; retractile in cavities which have the edges raised into short sheaths. Branchiae 5, large, ramose, tripinnate, set round the anus in a circle interrupted behind ; the anus is large, tubular, subpyriform, and is independently retractile within the plumes ; the general cavity has the wall fleshy and the orifice irregularly quinquilobate, and sometimes bearing on the lobes indistinct soft tubercles. Foot broad, truncated in front, rounded behind, with the margin, especially at the back, flat and subcrenulate. There is a very indistinct transverse marginal groove in front, through the centre of which passes the short broad proboscis ; and in front are two small, free, lateral, flat, rotundate lobes. Colour of the spirit specimens yellowish white, darker on the margins, on the tubercles, and on the foot; a greyish tinge appears on the large processes from within. On the back, between the processes, is a median longitudinal row of three large, very irregular, lozenge-shaped black markings, containing within each a subcentral large black blotch, as well as one or two short, broad, usually crooked black lines; they are often more or less continuous. Two other rows, each of 5 or 6 similar but smaller markings, the last two always confluent, run, one on each side, from in front of the rhinophores to behind the branchiae, outside the lateral rows of large processes. The spaces enclosed in these lozenge-shaped markings are always quite smooth. The laminated portion of the rhinophores are opaque yellowish brown, the pedicles light and transparent. The branchiae have the pinnulae lineated and tipped with black. Length (in spirit) 56 millims., breadth 44, height 16. Hab. ? (Obtained during the Antarctic Expedition.) |