NARRATIVE OF THE CRUISE. 
621 
Acctnthozone tricar inata, shown in fig. 208, enlarged. How far the present distribution 
into genera can be maintained under the light 
thrown on the subject by the details of struc- 
ture found in new forms, will have to be 
discussed in the detailed Report. Meanwhile 
it is interesting to observe that wherever the 
species have been dredged, either in localities 
or at depths not previously explored, such 
species are almost invariably found to be new 
ones. Species living at or near the surface of 
the ocean, and not therefore requiring to be 
taken with the dredge, are, as might be 
. • -i i , . .. , 0 . Fig. 208 . — Acanthotmie tricarinata, Stebbing. 
expected, widely distributed. Some that 
occupy very moderate depths are found to be identical or scarcely distinguishable in 
Fig. 209 . — Cystosoma neptuni (Guerin-Meneville), Sulim ; slightly reduced. 
form at the most widely separated localities, and it is possible that occasionally 
some specimens wdiile living may have a free passage from one extremity of the 
