174 THE CRINOIDEA CAMERATA OF NORTH AMERICA. 
introduced in the growing Crinoid in great numbers among the primary 
interradials and interdistichals, and between these and the basals, radials, 
and brachials. The interradial and interdistichal spaces throughout this 
group are greatly depressed, and the plates succeeding the radials folded 
into conspicuous ridges. This structure, combined with the more or less 
rudimentary character of the interposed plates, is so unique and remarkable, 
that all other characters, some of 
ae which in other groups are charac- 
8 
% teristic of very distinct families, 
S % : > 
ea 38: appear to be subordinated to it, 
% 4 5 
ota? and we are compelled to unite 
eee Oo 2 : 
Si under this family both monocy- 
Birr clic and dicyclic forms; those in 
: ‘ _ which the radials are all sepa- 
Bld RY R A, : ° 
. Caine m0 So rated, and those in which they 
oa0900° BEC seh: S Seams < : 
«0802 ae ; On are in lateral contact at four sides. 
m é 
yr : 083 720p T OT ; SORT 
a : a4 We think that few, after seeing 
ORO a large number of specimens, will 
ofG BE AO. ad ldts z 8} 4 oa) 
"Eo Boe : : 
Hea doubt the propriety of this course ; 
Ss 8 : 3 
Ss 3 for the structure in question pro- 
rou S . . . 
= & duces a habitus so distinct and 
Fig. 6. Reteoerinus Onealli. predominant, that it is only by 
means of these characters that the 
three genera of this family can be separated. 
In our classification of 1885,* we proposed the genus Canistrocrinus upon 
two species, which according to the descriptions differed from all genera 
previously known. In defining the genus we relied upon the correctness of 
the figures; but these have proved to be misleading in some very important 
points, and we are compelled to withdraw it. As to “ Canistrocrinus” Richard- 
sont (Glyptocrinus Richardsoni Wetherby), we are now convinced that it is 
a Glyptocrinus, and identical with Glyptocrinus subglobosus Meek. It has well 
defined interradials, and the anal plate rests wpon the radials, and not between 
them. The other species, “ Canistrocrinus” Patterson’ (Glyptocrinus Pattersoni 
S. A. Miller), may also prove to be a Glyptocrinus. The type specimens, 
which Mr. Miller was kind enough to send us for comparison, are not in 
a condition to make out the structure satisfactorily, being covered to a large 
* Revision, Part IIL., p. 88. 
