330 Cincinnati tSociety of Natural History. 



fill and beautiful species of crinoid that I have 3^et found in the upper 

 subcarboniferous. It is far less numerous than the species above de- 

 scribed. 



POTERIOCRINUS MILLERI, nOV. Sp. 



Under-hasals — Five, small, pentangular, nearly concealed by the 

 column. 



Basals — Five, pentangular, equal in size, small, about as wide as high. 



Radials — Five, pentangular, wider than high, equal in size, thickened 

 above, and united with the brac*"ials by widely gaping sutures. These 

 plates are incorrectly represented in the figures 12 and 13, as the}' are 

 pointed below. 



Brachials — Five, pentagonal, much higher than wide, laterally con- 

 stricted above their basal articulation, and each bearing upon its upper, 

 sloping sides, a pair of arms. 



The Arms — Ten, stout, long, composed of heavy irregularly pen- 

 tagonal plates, of which the form is best indicated in figure 12. Each 

 gives rise to a comparatively long and heavy pinnule. They are con- 

 tinuous without divisions to the tips. 



PinnulcB, — These are heavy and long, and composed of regular, 

 quadrangular plates. Their manner of origin, from lateral processes 

 of alternating arm plates, gives this species its peculiar appearance. 



Azygous Area. — This is comparatively large, exposing seven quite 

 regularly hexagonal plates in one specimen. As may be seen in tiie 

 same specimen, they are continued upward into a ventral sac which is 

 probably as long as the arms, but none of the specimens are in a con- 

 dition to indicate anything further in relation to them. 



The Column. — This is small, round, and evidently composed of 

 equal, thin plates. But a small portion, near the bod}' or' the crinoid, 

 has been found. 



This species has no very near relation, more than generically. with 

 any hitherto described. The specimens found were in a poor state of 

 preservation, and imbedded in a hard matrix. They were slightly de- 

 faced in the process of removal, but enough of their distinctive charac- 

 ters remain to determine their right to specific rank. The body is com- 

 paratively short and round; the plates exhibit evidences of tubercular 

 sculpture, neither of which facts appear in the figures. The species is 

 evidently rare, but tew specimens having been found. I have great 

 pleasure in dedicating this species to my friend and fellow-worker, S. 

 A. Miller, Esq. 



Locality and position of all the above: Upper part of the Kaskaskia 

 (Chester) Group, subcarboniferous, Pulaski couut3% K3^ 



