MUSEUM OF COMPARATIVE ZOOLOGY. 11 



fathoms; one specimen. Lat. 22° 9' 30" N., Lon. 82° 23' W. (1877-78); 

 depth 158 fathoms ; one specimen. Frederikstad (1878-79) ; depth 180 fathoms; 

 one epecimen. 



Thy one scabra, Verrill. 



The length of the larger specimen in the retracted state is about 90 mm. 

 The anus possesses fine calcareous teeth. The pedicels are cylindrical, slender, 

 rigid, and present in great number ; they attain a length of about 2 mm. The 

 calcareous ring closely resembles that in Thyone fusus. A single Polian vesicle 

 and one madreporic canal are present. The calcareous tables of the perisome 

 remind us slightly of those in the above-mentioned species, but the disks are 

 much more irregular, and pierced with a greater number of holes (sometimes as 

 many as twenty) of nearly equal size. The species undoubtedly bears a strik- 

 ing resemblance to Thyone fusus, but differs in having a strongly curved body, 

 and in that the posterior portion of the body is long and tapering; the tables 

 are also different. 



Habitat. Lat. 40° 1' N., Lon. 70° 58' W. (1880) ; depth 129 fathoms; 

 several specimens. Lat. 38° 21' 50" N., Lon. 73° 32' W. (1880) ; depth 197 

 fathoms ; one specimen. 



Thyone spectabilis, Ludwig. 



Habitat. Patagonia (Hassler Exp.); numerous specimens. Off Bermeja 

 Head, Lat. 41° 17' S., Lon. 63° W. ; depth 17 fathoms; several specimens. 



Thyone Hassleri, n. sp. 



The body in a contracted state is nearly cylindrical, slightly more tapering 

 towards the posterior extremity, and measures about 120 mm. in length. The 

 color is brownish, except the ends of the pedicels, which are whitish. The two 

 ventral tentacles are much smaller than the remaining eight. The body-wall 

 is rather thin, but hard in consequence of the close-lying deposits. In the 

 three specimens at my disposal, the ambulacra are marked by a low, longitudi- 

 nal furrow. The pedicels, which seem to be slightly larger and more closely 

 placed on the ventral surface, and very sparsely scattered in the anterior por- 

 tion of the body, are present on the ambulacra as well as the interambulacra ; 

 but they are possibly absent on a very narrow space along each interambula- 

 crum. The deposits are very closely crowded, and consist principally of two 

 kinds : small, rounded, discoidal, highly transparent bodies in several layers ; 

 and minute, scattered, perforated cups. The discoidal bodies, which are larger 

 in the interior layer, resemble at first sight agglomerations of drops of oil ; 

 generally, they are not perforated, though they not unfrequently have one, two, 

 or four holes. Those in the inner layer of the perisome are usually without 



