_ CRINOIDEA. 
which wrt marked on the middle of the under surface — a shale 
low groove, forming an interrupted circle around the The 
articular surface for the column is round, crenulated. at er mar 
gin, and occupies ebout one-half the wi idth of the base. The su- 
perior edge is nine-angled, six of the angles being salient, the 
others retreating. 
The Ist radial pieces are oe ew width double the 
height; three are hexagonal and two heptagonal, the inferior 
edges of the former slightly inked, in latter ‘celenies angulated. 
he superior edges of all of them are slightly concave, — er 
upper oblique edges rather short. The surface of each 
furnished with a prominent transverse curved ridge, the onal 
are re about one-fourth the size of the ome en 
rt on thei ser a - es two short wi 
chial pieces. seaies are pentagonal a and hexagons; vary much in 
their proportions, and the superior ones, being axillary pieces, a 
subject to icvégtdasieys as in the specimen aueue by the fig- 
ures 46andc. In this, we find one of the 3d radials supporting 
only a single brachial piece of the Ist order, instead of a double 
pair, as in the others, which piece is axillary, and bears on its up- 
per edge a double row of brachials of the 2d order. A similar 
—— occurs, also, in one of the brachial sone of i 2d 
Tr, in the same specimen, 
re oeae see “eee every two wedinl rows, we have 
three, and sometimes four, interradials, of which the p | 
ts § s superior ape Tests ¢ a feaighly apie 
er r side of sia ygonal 
