go BuivLKTTN 39 262 



is a common recent species along the eastern coast of United 

 States, becoming replaced in the West Indies by the Oltz'a reti- 

 cularis Lamarck. These two species are principally distinguish- 

 ed from each other, in that ihe sutures of O. sayana are quite 

 deepi}' channelled, above which projects the upper edge of the 

 wdiorls while in reticularis the sutures are merel}^ deep with 

 rounded or beveled shell margins. 



O . sayaiia var. immortua was described b}'' Pilsbry and 

 Brown, from Gatun beds in the vicinity of Cartagena, Columbia. 

 What appears to be the same shell is common in the exposures 

 found along the lower part of the Banana River. Like the brev- 

 istria it is rather darkl}^ colored, but no trace of a pattern is pre- 

 served. Our specimens averaged in length about 36 mm. The 

 largest specim.en measures 41 by 19.5 mm. 



Gatun Stage: Banana River, C. R. 



Olava teslacea Lamarck, var. costarscensis, n. var. Plate 7, figs, 12, 13 



Shell rather solid, with a moderately projecting spire, about 

 1-4 or less of the total length of the shell; whorls about 5, the 

 last, large, convex and widest about the middle; the spire-whorls 

 appear as if mesiall}^ divided b}^ an encircling weak callus about 

 the lower half; aperture broadest below, with the inner lip heav- 

 ily calloused above near its junction with the outer; the inner lip 

 is non-denticulated above, along its lower part with 3 or more, 

 irregular oblique, plaits; a broad band, arises from about the mid- 

 dle of the inner lip, passes obliquely dov/nward over the back of 

 the shell to the lovv^er end of the outer lip. 

 Length 42, diameter 19 mm. 



This Oliva is abundant in the Gatun beds of the Banana 

 River, C. R. It is closely related to the recent O. testacea Lam- 

 arck but seems to dilfer in being wider, shorter and with a lower 

 spire. 



The Oliva testacea Lamarck (in part O. hiatula of some au- 

 thors) is abundant along the Pacific coast of Panama, and in the 

 Manuals, its range is given as the West Coast. Recently a close- 



