NO. 3 CASSIDULOID ECHINOIDS — KIER 217 



three genital pores, no pores in left anterior genital plate; petals 

 long, straight, extending almost to margin, open, adjacent pore pairs 

 widely spaced, ambulacral plates beyond petals single pored ; periproct 

 marginal, longitudinal, slight groove extending adorally; peristome 

 anterior, slightly higher than wide ; bourrelets very strongly developed, 

 inflated ; phyllodes slightly widened, single pored, with few pores ; 

 buccal pores present ; tubercles slightly larger adorally, no naked, 

 granular zone in interambulacrum 5. 



Comparison with other genera. — Studeria is very similar to Plio- 

 lampas, as both genera have open petals, usually three genital pores 

 with no pore in the left anterior genital plate, similar phyllodes, and 

 a higher than wide peristome. Studeria differs in having a marginal 

 periproct, and more developed bourrelets. Perhaps these differences 

 are not of sufficient importance to warrant maintenance of Studeria. 



Remarks. — Mortensen (1948, p. 234), along with many earlier 

 workers, considered Studeria recens A. Agassiz as the type species 

 of Studeria. However, as Duncan mentions only one species, 5". 

 elegans, in his original description of this genus, 5". elegans must be 

 the type species by monotypy. 



I have been unable to find any specimens of the type species but 

 include below a description of a very similar species, 5. suhcarinatiis 

 (Goldfuss). 



Range and distribution. — Oligocene to Recent of Europe, Egypt, 

 and Australia. 



Synonyms of STUDERIA 



Hypselolampas H. L. Clark, 1917. Mem. Mus. Comp. Zool., vol. 46, No. 2, 

 p. 104. Type species by original designation, Studeria recens A. Agassiz. 



Remarks. — I have not seen any specimens of the type species, but 

 from a study of Agassiz's figures I can see no characters of sufficient 

 importance to warrant generic distinction for Clark's genus. 



Phaleropygus De Loriol, 1902. Notes pour scrvir a I'etude des echinodermes, 

 p. 15. Type species by monotypy, Phaleropygus oppenheimi De Loriol. 



Remarks. — I was unable to find any specimens of this species in 

 the De Loriol Collection in Geneve, but from a study of his figures, 

 this species appears to be congeneric with Studeria. Both Lambert 

 and Thiery (1921, p. 372) and Mortensen (1948, p. 372) also con- 

 sidered Phaleropygus a synonym of Studeria. 



