WHITE.] CARBONIFEROUS FOSSILS. 123 
attachment for the column ; body plates smooth or obscurely granular, 
and joined by slightly grooved sutures ; arms twenty, slender, each di- 
viding once on the second piece above their origin on the very small 
second radials, composed each of a single series of small pieces (as in 
P, nodobrachiatus Hall, lowa Report, p.542), bearing pinnules alternately 
on their inner ends.” 
Position and locality —Mr. Meek places this species (loc. cit.) in a list 
of Carboniferous fossils from the mountain called “Old Baldy,” near 
Virginia City, Mont. 
Genus LECYTHIOCRINUS White. 
» This genus was proposed in the Proceedings of the National Museum, 
vol. ii, p. 256, May, 1880, but it is desirable to repeat the generic diag- 
nosis in this connection. 
Generic formula. 
RePIICCES. JON Ji) ciate Litre dese eoidia. ¥ ansisinse walled he 3 
PRA TICCOS e282 SENS Se aol se eae SELEY gas yaiede 5 
retail pieces’. 1. 1935 milins a. tbewsd ce ees bw osinsdW jpdae ht 5 
Per MELerTaAdial Pieces (o4e sii<lsee 8 eee le wack. baa sg tect 0 
The basal subradial and first radial pieces are all well developed, those 
of neither set being minute. The dome is not known, but it was very 
small. The facet for the attachment of the column is small and round, 
but the column is not known. The facets for the attachment of the 
arms are small; the arms are not known, but they were evidently small 
and five in number. The character, arrangement, and shapes of the 
three basal pieces is precisely as in Platycrinus, and the arrangement of 
the five subradial pieces upon them is the same as that of the first 
radials upon the basals in Platycrinus. The arrangement. of the first 
radial pieces upon the subradials is essentially the same as that of Hris- 
ocrinus ; that is, they alternate regularly with them, and have no anal 
or interradial pieces intervening. The body, which is the only portion 
of the animal yet known, is thus composed of thirteen pieces, the ar- 
rangement of which is essentially that of five first radial pieces, all in 
close contact with each other, superimposed upon the calyx structure of 
Platycrinus. Or, if it be assumed that the basal cycle of pieces in the 
body of every true crinoid contains the elements of five pieces, and that 
in case there are only three apparent in the adult state, as in Actino- 
erinus and Platycrinus, there has been an early anchylosis of two adjacent 
pieces in two cases, we may regard Lecythiocrinus as a Cyathocrinid 
thus modified. Iam disposed to take this view, and consequently to 
refer the new genus to the Cyathocrinide. It is thought to be not im- 
probable that if other species of this genus are discovered, the base may 
be found to be composed of five separate pieces, instead of three; but 
no trace of the fourth and fifth sutures can be discovered in the base of 
the form here described. In case other examples should prove to pos- 
sess a five-parted base, the other characteristics of this form are still 
sufficient to hold it as a new generic form among the Crinoidea. 
Only one example of this interesting crinoid, consisting of the body 
alone, has been discovered. It is small and delicate in structure, the 
delicacy of the pieces composing it being similar to that of certain spe- 
cies of Platycrinus and Dichocrinus found in the Burlington limestone. 
In this respect it differs from all known crinoids of the Upper Coal- 
Ineasures, the pieces composing the bodies of which are thick and often 
Inassive. This delicacy of structure will probably be found to be char- 
acteristic of other species of the genus, should any ever be discovered. 
