NO. 4 ECHINOIDS, TRINIDAD AND VENEZUELA — COOKE II 



ment of the zygopores, which are biserial or staggered throughout in 

 P. hilli, uniserial near the apex in Phymosoma trinitensis. 



OLIGOPYGUS WETHERBYI KUGLERI Jeannet 

 PI. 3, figs. 9-1 1 



Oligopygiis ktigleri Jeannet, 1928, Soc. Paleont. Suisse Mem., vol. 48, pi. i, 

 figs. 1-7. 



Oligopygus kugleri is here treated as a subspecies of 0. wetherbyi 

 de Loriol (Cooke, 1959, p. 28, figs. 9-12) because all the specimens 

 from Trinidad, 9 entire individuals and several fragments, though 

 variable in proportions, are oval, strongly inflated, and have a smaller 

 peristomial depression than the typical form from Florida. The usual 

 shape of O. zvctherbyi, as shown by Cooke's figures, is rather low 

 and subpentagonal, though some are regularly oval. All of the rather 

 large suite in the U.S. National Museum are fairly large, and all have 

 a large peristomial depression. 



In Cuba, Oligopygus wetherbyi tends to be larger than in Florida 

 and even more variable. One long, narrow, very plump variety was 

 described under the name Oligopygus pinguis Palmer (MS.) by San- 

 chez Roig (1949, p. 165, pi. 28, figs. 2-2,). A shorter, nearly circular 

 variety from Jamaica has been named Oligopygus hypselus Arnold 

 and Clark (1927, p. 29, pi. 4, figs. 9-11). Both of these varieties from 

 Cuba and Jamaica have large peristomial depressions like the typical 

 form from Florida. 



Occurrence. — Trinidad : Soldado Rock, Gulf of Paria (Trinidad 

 Petroleum Co. K-903). 



Geologic horizon. — Late Eocene : San Fernando formation. 



Holotype. — Naturhistorisches Museum, Basel, Switzerland. 



Figured specimen. — USNM 638627, a topotype. 



OLIGOPYGUS HALDEMANI COSTULIFORMIS Jeannet 



PI. 3, figs. 1-3 



Oligopygus cf. coshilalus (Desor). Jeannet, 1928, Soc. Paleont. Suisse Mem., 



vol. 48, p. 8, pi. I, figs. 10-12. 

 Oligopygus costiiliformis Jeannet, 1928, Soc. Paleont. Suisse Mem., vol. 48, 



p. 9, pi. I, figs. 13-15. 



This subspecies differs from typical Oligopygus haldemani (Con- 

 rad) as described and figured by Cooke (1959, p. 29, pi. 8, figs. 6-8) 

 in its smaller peristomial depression, which, though deep, is not as 

 conspicuously elongated as that of the typical form from Florida. The 

 only specimen of the subspecies at hand measures 25 mm. in length. 



