454 Mr. C. Wachsmuth on the Internal and 
sion a. Dr. Schultze, who adopted Roemer’s classification, 
included in the Cupressocrinide the genera ‘‘ Synbathocrinus, 
Phill., and Phimocrinus, L. Schl.,” in which he is undoubt- 
edly correct, for stronger reasons even than he himself per- 
ceived. These two genera agree with Cupressocrinus not only 
in the simplicity of their arms, but also in the so-called “ con- 
solidating apparatus,” which he describes and figures in the 
latter. he apparatus is placed horizontally in Cupresso- 
crinus, upright and turbinate in the two other genera. When 
the consolidating plates in Synbathocrinus are preserved, the 
ventral side appears to have two separate apertures, a lateral 
proboscis and a central mouth. And so the genus was origi- 
nally described. This, however, is a misconception. By 
removing carefully all the arm-joints from a specimen of 
Synbathocrinus, 1 discovered the central aperture perfectly 
covered with a number of small plates ; and to this summit, as 
it might be called, were attached narrow lateral extensions, 
composed of alternating pieces, which, passing downward, 
covered the little grooves that lead to the arm-furrows. The 
consolidating apparatus here forms, in fact, a part of the solid 
vault. It is reasonable to conclude that in the allied genera 
Cupressocrinus and Phimocrinus, so closely related to Syn- 
bathocrinus otherwise, the central opening was closed, and 
that the consolidating plates were further overlaid with plates 
forming the floor of a passage in connexion with the arm-fur- 
rows and visceral cavity. The small plates which extend out 
to the arms are in the specimen but partly preserved, and the 
connexion with the arm-furrow is interrupted; but there can 
be no doubt that the channel underneath contained the food- 
groove and ambulacral canal which I have described in 
Cyathocrinus. The covering of the central opening of Syn- 
bathocrinus resembles in a remarkable degree that of the 
central aperture of the Blastoids; and it seems to me highly 
probable that the consolidating plates are homologous with 
the partly hidden deltoid pieces of the latter. 
Among the Cyathocrinides Roemer included genera of 
widely different types. Besides the typical one, he enume- 
rates nine genera, only two of which, SHeterocrinus and 
Graphiocrinus, have the characteristics of the Cyathocrinide ; 
and both of them evidently possess a solid dome, as is proved 
by their heavy proboscis. All the remaining genera belong 
to other groups. Macrostylocrinus resembles Ctenocrinus, 
Bronn, and Cytocrinus, Roemer, so closely, that they may yet 
prove to be identical. Roemer, however, places Ctenocrinus 
with Glyptocrinus among the Crinoids with a solid dome, and 
Macrostylocrinus among the Cyathocrinide. Macrostyloeri- 
