78 CRETACEOUS GROUP 



I formerly referred this species to S. cor marinum, 

 from which it is distinct. 



The S. stella of the former edition of this synopsis, 

 figured in plate iii, fig. 18, and in American Journal of 

 Science, vol. xviii, pi. iii, fig. 11, is the young of this 

 species, which is now found to be abundant in the arena- 

 ceous strata of Alabama, especially at Prairie Bluff. I 

 first found it in the calcareous beds on Timber creek, 

 New Jersey. 



2. S. ungula, (S. G. M.) PI. x, fig. 6. 



Specific character. Very compressed, with five excavated 

 ambulacra; apex central. 



From the arenaceous strata of the Chesapeake and De- 

 laware canal. The very elevated posterior end of the 

 former species is a striking and constant difference be- 

 tween it and the S. ungula. 



Ananchytes, Lam., Park. 



1. A. ductus, (S. G. M.) PL iii, fvg. 19. 



Amer. Journ. Science, vol. xviii, pi. iii, fig. 7. 



Specific character. Cordiform, with five pairs of dotted am- 

 bulacra, the posterior pair being in a deep sulcus extending to 

 the base. 



Common in the calcareous strata of New Jersey. 



2. A. fimbriatus, (S. G. M.) PI. iii, fig. 20. 



Amer. Journ. Science, vol. xviii, pi. iii, fig. 9. 

 Specific character. Cordiform, with five pairs of dotted am- 

 bulacra, the posterior pair being in a sulcus extending to the 



