68 S.S. Lyon and 8. A. Casseday on new species of Crinoidea, 
Art. IX.—Description of Nine new species of Crinoidea from the 
Subcarboniferous Rocks of Indiana and Kentucky; by SIDNEY 
S. Lyon and S. A. Cassepay. , 
Prerotocrinus. Lyon and Casseday. 
Asterocrinus, Lyon, Geol. Rep. Ky., vol. ili, p. 472, 
SINCE our description of Asterocrinus was published in the 
3d vol. of the Kentucky Report, we find the name to have 
appropriated previously. We therefore propose Pterotocrinus 
as the name of our genus, which has now four well authen 
ticated species, 
Generic formula. 
Basal pieces, 2 Mouth central, 
_ Radial pieces, 1st series, 5 Column round, (?) 
“2nd series, 10 Arms ciliated and single, 20 al 
e 3rd series, 20 Wings or lobed pieces, 5 } “femed, 
Anal piece, 1 or more. 
Pierotocrinus depressus, n. s. 
Body, depressed, subconical, twice as wide as high; below the free 
arms it preseuts the form of a ve shallow, flattened cup, the pieces 
composing it smooth and of equal thickness, in some cases nearly & 
plane, the margin curving suddenly upward at the junction of the arms; 
the vault rises from the a 
Radial pieces of the first. series, five ; subquadrangular, similar in 
: gh ; | 
series the ars, which before had been horizontal, become quite erech — 
and are composed of a double row of pieces which join by angular sides — 
in the center of the arms, ‘ 
Anal piece, one; obtusely angular below, fitting into a depression ee 
basal pieces, rounding to a point above, rising above the first radia 
