944 THE VOYAGE OF H.M.S. CHALLENGER. 
2435 fathoms; Globigerina ooze; bottom temperature 36°°5 F. One nearly complete 
specimen, and one stem with the basal ring attached, but wanting the rest of the calyx. 
Fie. 16.—Bathycrinus gracilis, Wyville Thomson ; twice 
the natural size. 
Remarks.—The shortness of the arms 
and the absence of well grooved pinnules 
indicate that the single specimen of this 
elegant little species is not fully developed. 
Sir Wyville Thomson’ said that “ there is no 
trace of pinnules, and the arms resemble in 
character the pinnules of hizocrinus.” 
There are, however, little stumps on the 
terminal jomts of one or two of the arms 
which give them the appearance of bifurea- 
tion, just as at the growing point of the 
arms of a young Comatula or Pentacrinus ; 
and I see no reason to doubt that these 
stumps are the commencing pinnules. 
I have already pointed out that the arm- 
joints of Bathycrinus gracilis are united in 
pairs exactly like those of Bathycrinus aldri- 
chianus and Rhizocrinus, except that in the 
latter genus the union is a syzygial one ; and 
the supposed resemblance of the arms of 
Bathycrinus gracilis to the pinnules of Rhizo- 
crinus thus disappears. 
As might be expected from its geogra- 
phical position, Bathycrinus gracilis comes 
nearer to Bathycrinus carpentert than to 
either of the Challenger species. The lower 
stem-joints are strongly constricted with 
markedly expanded ends as in that type ; but 
the absence of orals, the well defined medio- 
dorsal keel on the radials and arm-bases, and 
the serrate condition of the arms are sufficient 
to distinguish it without difficulty. 
During the expedition of the “ Talisman ” 
in 1883” a few much mutilated specimens 
both of Bathycrinus gracilis and of Rhizocrinus rawsont (Democrinus parfaiti, Perrier) 
* The Depths of the Sea, p. 452, 1873. 
* Comptes rendus, t. xevii. p. 1392. See also H, Filhol, Voyage du “Talisman” in La Nature, No, 572, 17th May 
1884, p. 391, 
