21 
and folding closely one over the other, posteriorly produced in the 
form of a tube, leaving a circular aperture ; colour yellowish. 
Animal.—Mantle not exposed ; cephalic disk quadrate, slightly in 
advance of the shell ; tentacular lobes four, produced from the 
corners of cephalic disk, round, short and bluntly rounded at their 
extremities, anterior pair slightly longer; foot small, not extend- 
ing posteriorly beyond the aperture, and not reaching in front the 
anterior side of the cephalic disc, of an oblong triangular shape, 
widest in front ; eyes minute at inner base of posterior tentacles ; 
anal opening at posterior aperture; colour white. 
Mus. Cuming. 
This anomalous animal was found on sea-weed dredged from a salt- 
water pond. It remained alive several days in a glass jar; it was 
very timid and slow in its movements. The animal would occasion- 
ally protrude slightly from the posterior aperture. 
Genus PHILINopsis. 
Animal.—Head-disk large, oblong oval or triangular, not extend- 
ing in advance of the foot. Posterior to the head-disk the body is 
extended in the shape of a convex fleshy lobe, commencing under 
the head disk (which overlaps it), and reaching to or slightly be- 
yond the posterior portion of the foot; truncated behind, and the 
truncation surrounded by an undulated or crenated crest. Eyes 
not visible. Mouth proboscidiform between cephalic disk and foot, 
with or without one pair of tentacles on sides of the mouth. Foot 
large, rounded and reflected at the sides. Branchial plume near the 
posterior end of the body, and curving around between the truncated 
end of the foot. Shell concealed in the truncated end. 
9. PHILINOPSIS SPECIOSA. 
Oblong, smooth. Head-disk about half the length of the ani- 
mal, of an oblong triangular shape, truncated in front, and corners 
obtusely rounded. The mantle-lobe is convex, rather narrowed 
anteriorly and truncated posteriorly, commencing under the head- 
disk and extending slightly beyond the posterior portion of the foot; 
the truncated end is prolonged behind laterally, and surrounded 
by an elevated undulated crest. No visible eyes or dorsal tentacles. 
Oral tentacles small, dilated, truncated, and placed at the sides of the 
mouth. The foot and the head-disk project in advance of the mouth, 
which can be protruded in the shape of a proboscis. Foot broad, 
oval, smooth, rounded and reflected at the sides. Branchial plume 
single, pinnate, arising from the right posterior end of the animal, 
and curving to the left between the foot and the truncated end of 
mantle-lobe. Excretory orifice posterior. Shell concealed in the 
truncated end, white, thin, fragile, pellucid, subtriangular, with a 
curved callous apex ; surface with furrows of growth. Colour above 
fawn, spotted and speckled with white; margins more or less varied 
with blackish and yellow; sides paler. Foot purplish fawn, and 
