388 [July, 



13. Ascidia succida. Test thick, cartilaginous, juicy, irregularly lobed, espe- 

 cially near the apertures, which are sessile, rather large, valvate, and difficult to 

 detect in the contracted specimen. Branchial sac reticulated, the reticulations 

 sharply projecting, the transverse striae, being as prominent as the longitudinal 

 ones, which are about ninety in number. Tentacles simple, filamentary, dis- 

 tantly arranged around the entrance of the sac, and only twenty in number. 

 Color of the posterior part of the body purplish ; the rest much paler ; aper- 

 tures ferruginous. Length lj inches. Found near low-water mark, among 

 stones. 



Hab. Australia, at Port Jackson. 



NUDIBRANCHIATA. 



: 14. Eolis cacaotica. Slender, tapering posteriorly to a fine point; of a clear 

 pale rose color on the body above, and on the anterior margin of the foot. Ten- 

 tacula rather short, rose-colored; the orals a little the longest ; dorsals tipped 

 with white, and having a ring of white at the base ; eyes large and conspicuous 

 Branchiae of a dark chocolate color, compressed, tipped with white ; arranged 

 in eight or ten clusters, and placed on the sides of the body, aateriorly, leaving 

 much of the back bare ; more numerous and crowded posteriorly so that the 

 clusters become indistinct. Length lj inches. Found under stones, in the lit- 

 toral zone. 



Hab. Australia, at Port Jackson. 



15. Tbitonia pallida. Truncate in front, tapering gradually behind ; of a 

 transparent white color, with a few Sake-white spots on the back ; oral veil 

 large, with eight elongated digitations, four on each side ; tentacles rather long, 

 with their sheaths having waved edges, and the filaments around the truncated 

 extremity of a dark brownish color. Branchiae small, margined with flake- 

 white, extending in a line on each side along the upper edges of the body; the 

 more conspicuous tufts being sixteen in number, having smaller ones between 

 them. A white line extends below and parallel to the branchiae, on the sides of 

 the body. Length, 1 inch ; breadth, 0.25 inch. On rocky bottoms, in the 

 coralline zone. 



Hab. False Bay, Cape of Good Hope. 



16. Triopa lucida. Depressed, broadest anteriorly ; clavate appendages 

 constricted at their bases, in number about forty, numerous and small in size at 

 the head, the posterior ones largest. Tentacula long, with about twelve lami- 

 nae. In front of each tentacle, near the margin, stands a clavate process much 

 longer than the others. Branchiae consisting of three plumes, about equal in 

 size. Color uniform transparent white, except that the tentacula, branchiae, and 

 appendages are all of a yellowish color towards their extremities. The tips of 

 the clavae appear open or hollow from their transparency. Length, 8 inch. 

 Found under stones, at low-water mark. 



Hab. Cape of Good Hope, at Simon's Bay. 



17. Goxiodoris ? obscuba. Oblong, quadrilateral; cloak broad, widely projec- 

 ting so as to conceal the oral tentacles anteriorly, and tapering from opposite 

 the branchiae, to a blunt point behind, disclosing the foot, which extends further 

 to a distance of one-fourth the length of the body. Dorsal tentaculae elonga- 

 ted, retractile, smooth and glossy to appearance, but having from twelve to four- 

 teen laminae. Branchiae retractile, consisting of twelve elongated, simply-pin- 

 nate leaflets, which form a cup around the anus. Color a dark greenish, or 

 yellowish grey, with numerous black and yellow dots; a row of black spots is 

 conspicuous, margining both the mantle and the foot. Head and oral tentacles 

 bluish-grey. Dorsal tentacles with red tips. Length, \\ inches ; breadth, 0.3 

 inch. Found among soft sponges in the circumlittoral zone. 



Hab. Australia, at Port Jackson. 



This species, with another closely allied and occurring in the same locality 

 form a genus probably new. It differs from Goniodorus, in having retractile ten- 



