Mr, Alder and Mr. Hancock on new Mollusca. 33 



mouth extended at the sides into two leaf-like appendages. Foot 

 extending a little beyond the cloak behind. Length nyths of an 

 inch. 



At low-water mark and from deep water, CuUercoats ; very rare. 



Approaching very nearly to D. pilosa, but differing in the stouter 

 papillae, and in the number and form of the branchial plumes, which 

 are also entirely devoid of the stellated appearance of that species. 



POLYCERA OCELLATA. 



Body greenish black, varied with chestnut and yellow, and co- 

 vered with irregular ocellated spots of a pale yellow or fawn-colour, 

 capable of being raised into tubercular points. Veil denticulated, 

 short, yellowish white, interrupted in front, continued along the 

 sides of the head and back in an elevated ridge with scalloped edges, 

 and terminating in two or three irregular lobes or tubercles on each 

 side behind the branchiae ; the two lines approach each other in the 

 middle of the back so as to form an imperfect figure of 8. Tentacula 

 two, dorsal, large, club-shaped, strongly laniellated towards the tips. 

 Branchiae consisting of three or four large flocculent plumes, tripin- 

 nate, pale greenish black with light margins. Foot yellowish, in- 

 clining to red, mottled with black. Length -j-yths of an inch. 



Under stones at low-water mark, Cullercoats and Whitley ; rather 

 rare. 



The Triopa Nothus of Dr. Johnston may be the young of this spe- 

 cies. At i^resent however we prefer considering them distinct, not 

 having been able to detect any spicula in our animal. 



Tritoxia felina. 



Body slender, rather opake, firm to the touch, compressed at the 

 sides and slightly rounded on the back, rough with small warts ; 

 richly spotted and marked with dark red or reddish brown, and 

 speckled with white tubercular spots. Tentacula yellowish, lamel- 

 lated, issuing from long, cylindrical, rather tight sheaths, divided at 

 the top into five short branches. Veil consisting of about four un- 

 equal branched appendages on each side. Branchiae stout, two or 

 three times branched and warty ; six on each side of the back, the 

 hinder ones very small. Foot transparent white, slender. Length 

 nearly an inch. 



On corallines from deep water, Cullercoats. 



This may prove to be the T. arborescens of British authors, but it 

 is surely distinct from that of Cuvier. 



T. pulchella. 



Body slender, soft, transparent, pale rosy flesh- colour, with mi- 

 nute, opake, yellowish tubercular spots. Tentacula strongly lamel- 

 lated, issuing from branched, deeply divided sheaths ; the tubular 

 part rather short. Frontal veil consisting of four slender branched 

 appendages, with four intermediate linear ones. Branchia; slender, 

 transparent, flesh-coloured, spotted with opake yellow; five pairs, 

 the last very short. The front ones consisting of three branches 



Ann. (S)- May. N. Hist. Vol. ix. D 



