164 RADIATA. 



No. 816. Scutella disca, Mather. 



This American Clypeastroid is from the Tertiary of 

 Georgia. Price, $0.30. 



No. 817. Sismondia costulata, Desor. 



(Syn. EcMnocyamus costulatus, Desor.) A Clypeastroid, convex above, con- 

 cave underneath ; petals broad and elliptical ; central summit ; marginal anus. 

 From the Tertiary (?) of Europe. Price, $0 90. 



Dysasteridoe. 

 No. 818. Collyrites carinata, Desm. 



This small species is essentially cordiform, with a keel more or less marked. 

 From the Oxfordian (Middle Oolite), Wurtemberg. Price, $0.15. 



No. 819. Collyrites elliptica, Desm. 



(Syn. Dysaster ellipticus Agass.) A large in fiated species. From the Cal- 

 lovien (Middle Oolite), France. Price, $0.50. 



Galleridse. 



No. 820. AnorthopygUS COStellatUS, Desor. 



(Syn.Pygaster costellatus, Agass.) This species has a circular, depressed form, 

 with small tubercles regularly disposed. It is from the Cretaceous of France. 



Price, $0.25. 



No. 821. Discoidea cylindrica, Agass. 



This Echinus has a hemispherical test, the height 

 sometimes exceeding its diameter, and very small 

 tubercles arranged in concentric series. From the 

 Chalk-marl (Cretaceous) of Eouen, France, and now 

 in the Ward Museum of the University of Rochester. 



Price, $0,25. 



No. 822. Discoidea cylindrica, Agass. 



(Var. alta.) From the Chalk-marl (Cretaceous), France. 



Price, $0.35. 



No. 823. Echinoneiis cyclostonrus, Leske. 



This small species has an elongated, inflated test, with numerous tu- 

 bercles, mamillated but not perforated. From the Calcareous tufa (Recent), 

 Guadaloupe, W. I. Price, $0.20. 



No. 824. G-alerites subsphseroidalis, D'Archiac. 

 From the Lower Chalk, Fauge, France. 



Price, $0.20, 



