240 



Bulletin 39 



the present study of the occurrence of West Coast species in the 

 Caribbean Miocene, proving conclusively from a purely paleon- 

 tological standpoint the rather late separation of the Atlantic 

 and Pacific through the final uplift of the isthmian lands. 



The recent A. Listeri Gra}^ is a smaller, more elongate 

 species and with finer and sharper concentric lamellae. 



Length 107 mm, height 102 mm, diameter 69 mm. 



Gatu7i Stage: Water Cay. 



Antigona tarquina Dall Plate 30, figure 10 



Vemis mag-nifica Gabb, 1673, Trans. Amer. Phil. Soc, vol. 15, p. 249. 



Not of Sowerby, 1853. 

 Cytherea tarquina Dall, 1900, Trans. Wagner Free Inst,, vol. 3, pt. 5, 



pi. 38, figs. 2, 2a; vol. 3, pt. 6, p. 1274. 

 Antigona tarquina Dall, 1915, Bull. 90, U. S. Nat. Mus., p. 147. 

 Antigona tarquina Maury, 1917, Bull. Amer. Pal., vol. 5, p. 381. pi. 



37, fig- 4. 



A small shell identical or closely related to A. tarquiyia 

 Dall was collected from Zone 3 of Saury Creek. It is similiar 

 to Dr. Maury's specimen of A. tarquina from Santo Domingo. 



Typical A. tarquina Dall is a common fossil of the Orthau- 

 lax pugiiax fauna of the Tampa Silex beds of Florida. It was 

 also collected by Professor Gabb and Dr. Maury from the Mio- 

 cene of Santo Domingo. 



Gatun Stage: Zone E, Saury creek ^ near Cahuita, C. R. 



Section VENTRICOLA, Roemer 

 Antigona rugosa Gmeiln Plate 30, figure 4 



Venus rugosa Gmelin, 1792, Syst. Nat., p. 3276. 



Venus rugosa Reeve, 1863, Conch. Icon., vol. 11, pi. 7, fig. 23. 



Several specimens from the coralline limestones of Port 

 Limon. They are practically identical with recent examples of 

 A. rugosa from the West Indies. This species is distributed 

 throughout the West Indies but is also found living in the Gulf 



