10. Cynthia dumosa. Globular, of a yellowish-brown color ; surface villous, 

 and provided with numerous stout, sub-conical processes of the test, which have 

 short irregular branches. Apertures cross-shaped when contracted ; the bran- 

 chial more than twice the size of the anal. Branchial sac with twelve very 

 large folds, which are much broader than their interspaces. Tentacula also 

 twelve in number, including four or five small ones ; biserrate, folded longitudi- 

 nally, and curved so as to present their pinnae toward the branchial cavity. Di- 

 ameter 1 inch. Found in the circumlittoral zone, on muddy bottoms. 



Hab. Australia, at Port Jackson. 



11. MoLGULA iNCONSPicuA. Small, free, bullet-shaped; test thin, brittle, with 

 a thin but solid coating of sand ; apertures clear, transparent while ; the 

 branchial six- rayed; the anal with four well-marked lobes. Branchial sac with 

 eight folds equalling their interspaces in width. Diameter, half an inch. 

 Found in the circumlittoral zone, on sandy bottoms. 



Hab. Australia, at Port Jackson. 



12. AsciDiA SYDNEiENSig. Gregarious, several specimens growing together in 

 one mass. Test irregular in shape, thin, often translucent, of a pale purplish 



.color. Apertures on long tubes, which are marked with longitudinal ridges 

 corresponding in number with the rays of the apertures ; the branchial having 

 seven, the anal six rays. Branchial sac finely reticulated, the transverse threads 

 much less prominent than the longitudinal ones. Tentacula simple, thread-like, 

 about one hundred in number, curved and projecting into the cavity so as to 

 form a dome-like filter for the water as it enters the branchial sac. Length 1^- 

 inches. Found near low-water mark, among rocks. 

 Hab. Australia, at Port Jackson. 



13. AsciDiA succiDA. Test thick, cartilaginous, juicy, irregularly lobed, espe- 

 cially near the apertures, which are sessile, rather large, valvate, and difiBcult 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 1|- 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 

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

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

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

 clusters become indistinct. Length 1| inches. Found under stones, in the lit- 

 toral zone. 



Hab. Australia, at Port Jackson. 



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

 transparent white color, with a few flake-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 beloiv and parallel to the branchia', on the sides of 



