EXPLANATION OF TLATES 225 



of one adult with portions of five other individuals in vari- 

 ous stages of growth. Noteworthy features of the adult 

 are the form and direction of the rajs, the large submar- 

 ginal and small marginal plates and the sculptured surface 

 of the interradial plates. The two very young individuals 

 are specially interesting, as showing the relative width of 

 the marginal area and the straight rays abutting against 

 the broad border, x 2 



This is not a reproduction of the figure given by Hall, in the 24th 

 report of the New York state museum, but is a new drawing. 



Hamilton beds. West Hamilton, Madison -co. N. Y. 



Agelacrinites buttsi sp. nov. 

 p. 196 



Fig. 



7 A cluster of individuals attached to a shell of Ptychopteria. 



Natural size 



8 The largest of the individuals x 2. Showing the very broad 



border composed of small imbricating plates, R 1-4 contra- 

 solar, R 5 solar and the imbricating interradial plates 



9 A younger individual, in which the border is relatively much 



broader and the rays direct, x 2 

 Supradevonic sandstone (Cattaraugus beds) Mt Moriah, Cat- 

 taraugus CO. N. Y. 



