thp: 
AMERICAN GEOLOGIST. 
Vol. XXXIV. NOVEMBER, 1904. No. 5. 
THE ECHINODERIVIATA OF THE MISSOURI 
SILURIAN AND A NEW BRACHIOPOD. 
By R. R. Rowley, Louisiana, Mo. 
Pisocrinus granulosus, n. sp. 
Pl.^tk XVI. Figs. 1, 2, 3 >: 2. 
The five l)a.sal plates of this little oriiioid are quite large, 
extending' considerably beyond the columnar pit. As in other 
species of the genus, they differ much in size and shape. 
The two large radials rest on the basals, the three smaller ones 
being triangular and lying between the two larger. The two 
posterior radials rest upon a rather broad, pentangular anal 
plate. The radial extensions upward, separating the arm bases, 
though not long, are stout as in the figures. The entire surface 
of the plates is beautifully granular. 1"he plates are heavy 
and the body outline hemispherical. 
b'igure 3 in its plate arrangement differs widely not only 
from the specimen Figs, i and 2 but even from the genus 
Pisocrinus. However we take it to lie a mere abnormality. 
Three of its radials are large and rest on the basals. while the 
other two are small, resting between the two larger radials 
without touching the basals. There is no anal plate, whatever. 
In all the specimens of Pisocrinus figured on our plate the 
basal region is excavated. 
TIic specimens came frum the red. slialy limestone of the Xiagara 
age, near St. Mary's, Ste. (Jencvieve Co.. Mo. 
Pisocrinus gorbyi ? S. A. Miller. 
Plate XVI. Figs. 4, ,T, 6, 7 X 2. 
This is another granulose species, somewhat smaller than the 
f<irmer, distinctly star-.shaped and less rotund. In small speci- 
