680 



PROCEEDINGS OF THE NATIONAL MUSEUM. 



VOL. XXXII. 



and grayi-^li brown. Leng-th of largest specimen, nearly f ulh^ extended 

 (preserved in formalin), about 250 mm. 



Localities.— Type (Cat. No. 21215, U.S.N.M.) from Station 4:l;^>(), 

 vicinit}' of Kanai Island, 283 to 309 fathoms, fine gray sand, bottom 

 temperature ■±6.1'^; 13 specimens. Taken also at the following stations 

 (in all 50 specimens): 



List of stations. 



As noted in the diagnosis above, the number of tentacles varies from 

 18 to 20, and is f requentlj^ 19. Branches of crown are all short, the 

 latter being subcircular and rather fiat topped. Width of circle 

 of tentacles over all about 25 mm. Ambulacral appendages very 

 scarce on dorsal surface and scattered, but at hinder end of body 

 the}^ become more numerous, yet remain inconspicuous. Over most 

 of dorsal surface it is difficult to distinguish ain' pedicels at all without 

 the aid of a glass; but some specimens appear to have more than 

 others. The wart-like thickenings seem to represent mucli contracted 

 papilUe possibly of a sensory nature, since they are more retracted 

 than the pedicels. On median ventral region the pedicels are easy 

 to see, l)ut are very small, g-radually increasing- in size toward the 

 ventral-lateral radii. In formalin specimens, which wonderfully retain 

 the life appearance, the mid-ventral radial line is conspicuous owing 

 to transparency of integument. Perisome is minutely roughened by 

 spires of tables. 



The calcareous ring- is rather soft, and in alcoholic specimens is often 

 mu(;h shrunken, giving- an appearance of variability. Radial pieces 

 much larger than interradial, with an abrupt deep notch on posterior 

 border on either side of which is a little horn, forming an incipient pos- 

 terior prolongation. This is apparentlj^ obsolete in some specimens. 

 Anterior border has a central narrow notch and on either side a very 

 shallow undulation. Interradial pieces with a prominent tooth anteri- 

 orly but not noticeably excavated posteriorly. One large Polian vesicle. 

 Madreporic canal runs forward and upward in dorsal mesentery, the 

 ovoid madreporic body being attached to bod}- wall at anterior edge of 

 mesentery. Ring canal and radial water canals between the former 

 and calcareous ring large. No tentacle ampullar extending into the 

 body cavity, only rudiments, filling the anterior excavations in calca- 

 reous ring. Thus there are two larger ampulla? (interradial) alter- 



