MONOGRAPH OF THE EXISTING CEINOIDS. 765 



Pi ATE 30. 

 Lance of Antedon. 



FIG. 1191. Antedon bifida, young larva recently attached. (After Wyville Thomson.) 

 1192. Same, somewhat more advanced. (After Wyville Thomson.) 

 1193. Antedon bifida, pentacrinoid larva immediately after complete separation of oral 



valves, with cup closed. (After Wyville Thomson.) 

 1194. Antedon mediterranea, larva of tenth day seen aa transparent object ; plates on 



farther side of body are omitted. (After Bury.) 



PLATE 31. 

 Larva of Antedon. 



FIG. 1195. Antedon bifida, a pentacrinoid before expansion of ventral disk with cup expanded 

 and showing arrangement of nonextensile tentacles. (After Wyville Thomson.) 



1196. Antedon, mediterranea, basal from larva of tenth day. (After Bury.) 



1197. Same, an infrabasal from larva of same age. (After Bury.) 



1198. One of uppermost columnals from same larva with rudimentary longitudinal proc- 

 esses. (After Bury.) 



1199. One of uppermost columnals from larva of same species of seventh day. (After 

 Bury.) 



1200. Infrabasal from same larva : this would equally well represent a basal some 24 hours 

 earlier. (After Bury.) 



PLATE 32. 



Larttf of Antedon bifida. (After Wyville Thomson.) 



FIG. 1201. Pentacrinoid larva immediately after complete separation of orals, expanded (fig. 



1193.) 



1202. Portion of oral disk of same stage in state of complete expansion, seen from above, 

 1203. Pentacrinoid larva immediately before expansion of ventral disk. 



PLATE 33. 

 Lan-<e of Antedon bifida. (After W. B. Carpenter.) 



FIG. 1204. -Group of pentacrinoid larvse in different stages. 



1205. Skeleton of early pentacrinoid larva, from dried specimen, showing way in which 



calyx at that stage can be completely closed in by folding together of orals. 

 1206. Skeleton of young pentacrinoid larva, showing incipient development of dorsal cirri, 



and radianal being lifted up from between radials. 



PLATE 34. 

 Pentacrinoid larv<e of various comatulids. (After P. H. Carpenter.) 



FIG. 1207. CrotaJometra porrecta. 

 1208. Same. 

 1209. Same. 



1210. Hathrometra prolixa. 

 1211. Glypt&metra. tuberosa. 

 1212. Leptometra celtica. 

 1213. Hathrometra prolixa. 

 1214. iThaumatometra, sp. 

 1215. HeHomctra alaciaH.t. 



