CHAP. IX-] THE DEEP-SEA FAUNA. Ae 
representatives of this group, until now supposed 
to be on the verge of extinction, and that all the 
known species are from depths beyond the limit 
of ordinary dredging, we are led to anticipate that 
erinoids may probably form rather an important 
element in the abyssal fauna. 
Isa 4 
bf ag 
2 SOG a1) 
= 
Fic. 74.—Archaster bifrons, WYVILLE THOMSON. Oral aspect. 
Three-fourths the natural size 
(No. 57, 1869 ) 
The general distribution of the deep-sea Asteridea 
has already been referred to. Perhaps the most 
obvious peculiarity which they present is the great 
preponderance of the genera Aslrogonium, Archaster, 
Astropecten, and their allies. Genera belonging 
to other groups do not apparently become less 
