24 



Bulletin 39 



19s 



Dolumi camura Giippy Gurabo 



Dolium elliptica Pilsbry and Johnson Gurabo 



Cercado and Gurabo 

 Gurabo 

 Gurabo 



Cercado and Gurabo 

 Cercado and Gurabo 

 Cercado 

 Gurabo 



Cercado and Gurabo 

 Cercado and Gurabo 

 Cercado and Gurabo 



Cypraea Henekeni Sowerby 



Cypfaea doininice7isis Gabb 



Strombus pugiloides Guppy 



Serpulorbis papulosa Guppy 



Petalocojichiis scidpturaUis H.C.Ivea 



'^Architectonica granidata Lamarck 



'^"Xenophora conchyliophora Born 



"^Natica canreiia Linne 



Natica You7igi Maury 



Polinices szcbclausa Sowerbj' 



Polinices Stanislas- Metinieri Maur}' Gurabo 



Neritina viridemaris Maury Corcado and Gurabo 



Neverita nereidis Maury Cercado 



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

 tion. Cancellaria {Aphei'a) islacolonis Maur}^ Neverita nereidis 

 Maury and Corbula 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 Ca)^ 



Glycymeris Janiaicensis Dall Winter Ca}'' 



Protocardia gtirabica Maur}" 



Antigona tarquinia Dall ? 



Telli7ia cei'cadica Maury 



Se^nele Claytoni Maur}^ 



Corbida viminea Guppy 



Ringicida do7ninicana Maury 



Water Cay and Gatun 

 Saury 

 Saury 



Hotel Creek 

 Middle Creek 

 Middle Creek, Red Cliff 

 Creek and Estrella River 



^Recent. 



