MUSEUM OF COMPARATIVE ZOOLOGY. is 
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 specimen. 
Thyone 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 about2 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, Lupwie. 
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 hy 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 
