60 The Ohio Journal of Science [Vol. XIX, No. 1, 



The material worked on comes from several definite horizons. 

 These are: 



1. Several localities in the Corryville. 



2. At the base and near the top of the Saluda in Franklin 

 and Ripley Counties, Indiana. 



3. In the Oakland (Elkhorn) division on Dutch and 

 Cowan's creeks, Clinton County, Ohio. 



4. At the top of the Richmond near Lawshe, Adams 

 County, Ohio. 



5. Near the top of the Richmond (Elkhorn) near Eaton, 

 Ohio, and on Elkhorn creek, Indiana. 



Additional material has been secured from collections by 

 C. B. Dyer, of Cincinnati, and D. T. D. Dyche, of Lebanon, 

 Ohio. These specimens are probably from the Corryville 

 levels or below them (No. 1). 



When conditions of water, its clearness and depth were 

 satisfactory these little echinoderms were quite abundant. 

 They lived attached to the larger shells at the bottom, clam 

 valves being most common locations in the Richmond and the 

 large brachiopod, Rafinesquina alternata, carrying most of 

 the Maysville specimens. They have been found on the outer 

 surface of a sponge, Dystactospongia madisonensis Foerste, on 

 corals, Tetradium, on several different clams, Ischyrodonta, 

 Byssonychia, etc., on Hebertella, PJatystrophia and other large 

 brachiopods and, notably on Cowan's Creek, in Clinton County, 

 loose and inverted. 



In this case it would seem possible (1) that the shell on which 

 the Agelacrinites was attached was turned over by wave action 

 and that in death the animal separated from its point of attach- 

 ment and so was found lying aboral side uppermost or else 

 (2) that the animal was not permanently attached, but could 

 free itself and reattach. 



Zittel's description of the family of the Agelacrinidas Hall 

 is as follows, (Vol. I, Part I, p. 187): "The calyx composed 

 of a large number of small, irregularly arranged plates and either 

 furnished with a short stem or fixed by a broad base. Plates 

 pierced by pores usually united in pairs. Mouth central, anus 

 excentric, provided with a valvate pyramid (of plates). Arms 

 placed in radial grooves on the exterior of the calyx and pro- 

 tected by covering plates." 



