BEEDE: new fossils from the KANSAS COAL MEASURES. I25 



plates, which are twice as long as high in the lower portion of the 

 arms and each supporting a single pinnule. The pinnules are not 

 well preserved, but are stout, composed of rather large, square 

 plates near their junction with the arms, while further away they 

 assume a cylindrical form. When not worn the entire specimen is 

 covered with coarse granulations which are usually a little pro- 

 longed. 



Measurements: „ . ^ ,„.^ , Lensth 



Height. Width, (beyond calyx). 



Basals , 1 1 mm. lo mm. 



Radials 8 " i6 " 



Costals 5 " 15 " g mm. 



1. Distichals i to 2 " 8 " 



2. Distichals 2 " 4 " 



Average lower arm plate 2 " 4 " 



Upper Coal Measures, from Topeka, Kansas, from the horizon 

 of the Osage coal. 



This species agrees in many respects with Ceriocrinus craigii 

 (Worthen) W. and S., and C. heniisphericus (Shumard) W. and S., 

 but each of these possess an anal plate, while the specimen in 

 hand, though preserved in good condition, shows no indication of 

 such a plate. It is placed provisionally with the genws En's ocri tins 

 as the nature of the infrabasals can not be made out from this 

 specimen. It may prove to belong to Stenuiiatocrinus when the 

 nature of these are determined. In discussing these two genera 

 Wachsmuth and Springer make the following observation: "We 

 also observe a difference in the construction of the arms, which in 

 the former {^Stcmuiatocriiius) are composed of a double series of in- 

 terlocking plates, while in the two species of Erisocrinus, in which 

 the arms have been found, they are composed of single transverse 

 plates. Both species, however, are from the Burlington limestone, 

 and are very small, and it is extremely probable, from analogy 

 with contemporaries, that the arms in the species from the Coal 

 Measures, where the genus flourished more abundantly, were, as 

 in Steiniuatocrinits, composed of interlocking pieces, and that the 

 Burlington species represent the young form. This would make 

 the difference in the underbasals the only visible distinction."* 

 E. iypus and the Topeka, specimen here described exactly fulfil 

 this prediction, if it be a true Erisocrinus, as it probably is. 



♦Revision Palteocrinoidea I, p. HO. 



