14 
THE GEOLOGIST. 
the rays reach the number of 80, or sometimes 100. These rays 
are long, and very elegant ; and the joints have a wedge-like form, 
and are so aiTanged that the thick end of the one con-esponds 
with the thin end of the next. In W. goniodactylus the arms 
bifurcate so as to make a total of 50, while the joints differ from 
those of all other species in the angular formation of their dorsal 
aspect — the zigzag pattern formed by their peculiar style of 
articulations — and the thickening of the last axillary joint of each 
ray. The number of joints in each ray is never less than 4, and 
never more than 10. Each joint of these rays is furnished with a 
long, slender, many-jointed, flexible pinnule, which springs 
alternately from opposite sides of the arm, so as to make two 
rows. In W, goniodactylus these pinnules are more delicate than 
in the other species. The anal region, which is that part of the 
calyx not covered by the radial plates, is composed of small 
diversely-formed pieces ; which are miited above to the dome, and 
laterally to those plates from which the arms spring. In W. 
expansus these plates are fewer in number, and larger than in W. 
macrodactylus. The dome, which is the upper part of the 
skeleton, has not yet been found entire in this genus. A few 
plates of hexagonal and pentagonal form have been noticed ; but 
neither its form nor size can be indicated with any certainty. It 
appears to be large ; the plates are beautifully marked in a relief, 
with a star-like projection, not unlike the dog-tooth ornament 
which characterizes early English architecture. 
The stems are composed of thin cylindrical joints, alternately 
larger and smaller, giving them a ring-like appearance. The thick- 
ness does not differ much in any of the species. The length is 
considerable, and very variable. But the special character of this 
stem is that, unlike the stem of all known crinoides, it is much 
thinner at the base than at the summit. No actual termina- 
tion can be said to have been discovered; but in all the species 
the stem is invariably tapering, so that the longer it is the thinner 
it becomes. This circumstance would lead us to imagine, that the 
creature floated freely in the water, and that the stems were used 
to balance it, and keep it upright while it floated. Should this fact 
be established, it will place this genus as a link between the free 
Comatula and the fixed Crinoid. It may, however, have had the 
