24 Eui^LETiN 39 196 



Doliu7n cajnura Gnppy Gurabo 

 Dolium elliptica Pilsbry and Johnson Gurabo 

 Cypraca Henekeni Sowerby Cercado and Gurabo 



Cypraea dominicensis Gabb Gurabo 

 Strojnbus pugiloides Guppy Gurabo 

 Serpiilorbis papulosa Guppy Cercado and Gurabo 



Petaloconchus scidpturatus H.C.Ivea Cercado and Gurabo 

 "^Architectojiica granulata Lamarck Cercado 

 ^Xe7top/iora conchy I lop ho?'a Born Gurabo 

 "^^Natica ca^irena Linne Cercado and Gurabo 



Natica Youngi Maury Cercado and Gurabo 



Polinices subclausa Sowerby Cercado and Gurabo 



Polinices Stanislas- Meiinieri Maury Gurabo 

 Neritina viridemaris Maury Corcado and Gurabo 



Ncverita nereidis Maury Cercado 

 Most of the above listed species belong to the Gatun forma- 

 tion. Canccllaria {Aphera) islacolo7iis Maury, Neverita nereidis 

 Maury and Corbitla viminea Guppy occur in the Upper Uscari 

 and in the Lower Gatun or transitional beds of eastern Costa 

 Rica. This leaves but the following 8 Cercado species in the 

 Gatun fauna, or a proportion of about 3.25 to 1. 



Area Henekeni Maury Winter Cay 



Glycynieris jamaicensis Dall Winter Caj^ 

 Protocardia gurabica Maur}^ Water Cay and Gatun 

 Antigona tarquinia Dall ? Saurj^ 

 Tellijia cetradica Maury Saury 

 Semele Claytoni Maur}^ Hotel Creek 



Corbula viminea Guppy Middle Creek 



Ringicula do?ninicana Maury Middle Creek, Red Cliff 



Creek and Kstrella River 



^Recent. 



