MUSEUM OF COMPAKATIVE ZOOLOGY. 3 



prove not to "be of specific value. But considering the differences whicli really 

 exist with regard to the outer appearance, and taking into consideration, 

 that the deposits were dissolved in the types brought home by the Chal- 

 lenger expedition, I propose to refer it, for the present at least, to a new 

 species. 



The Blake specimen differs from Benthodytes sanguinolenta in being devoid 

 of the transverse ventral row of papillae situated immediately behind the 

 crown of tentacles ; the position of the anus is more ventral, and it carries 

 only a very few slender dorsal processes, which seem to be confined to the two 

 ambulacra alone. The madreporic canal appears to open exteriorly (?). The 

 integument is rather rough from numerous larger and smaller deposits, which 

 consist of four curved arms and a smooth central spine directed outwardly ; 

 each of the four arms generally bears a large process directed outwardly and a 

 few smaller ones. In the ventral perisome, the deposits are more irregularly 

 formed, and have the shape of unbranched rods and three- or four-armed bod- 

 ies. Thus the deposits of this species closely resemble those of Eaphmnides 

 depressa. 



Habitat. Bequia ; depth 1591 fathoms. One specimen, 220 mm. long and 

 53 mm. broad. 



Benthodytes sp. (?). 



The very defective state of the specimens at my disposal renders a detailed 

 examination impossible. They seem to bear the closest resemblance to Bentho- 

 dytes abyssicola. There appear to be fifteen tentacles. The dorsal ambulacral 

 appendages are few and minute. The deposits present themselves as scattered, 

 very large and robust four-armed spicules with a long spinous central spine, 

 the extremity of which is usually split into two or three spinous tops, giving 

 to the surface of the skin a remarkable roughness. The central spines are 

 almost visible to the naked eye. 



Habitat. Bequia j depth 1507 fathoms ; three very incomplete specimens. 



Paelopatides Agassizii, n. sp. 



One of the largest specimens has the following measurements: length 

 270 mm.; breadth 120 mm.; height varying between 5 and 10 mm. The 

 body is thus very depressed, almost flat, and very broad; its anterior and 

 posterior ends are obtusely rounded or truncated. The pedicels are only 

 present on the odd ambulacrum, where they form a thin double row over three 

 fourths of its length; the anterior fourth of the odd ambulacrum is naked. 

 The thin wide brim, which surrounds the body and reaches a breadth of about 

 40 mm., is pierced by a number of canals which branch off from the two 

 ventral lateral ambulacra, cross the brim, and run out in very minute papillae 

 situated in the margin of the brim. These papillae form a simple row in 



