26i 



Costa Rica Miocene — Olsson 



89 



variety Giraudi Cossmann 



Oliva Giraudi Cossmann, 1913, Journ. de Conchyliologie, vol. 61, p. 

 56, pi. 5, figs. 4-8. 



A fairly common species in Cost Rica. Typically the shell is 

 short; moderatly convex, a short projecting spire and concave 

 spire-whorls. 



Unusually broad forms as illustrated by figure 4 may be sep- 

 arated by the name of Giraudi Cossmann. 

 A large tj^pical shell measures: 

 Length 35, diameter 17 mm. 



Gatun Stage: Coll. 6, Red Cliff Creek, C. R. 



Headwaters of Middle Creek, C. R. 

 Coll. 5, Grape Point Creek, C. R. 



Oliva gatunensis Toula Plate 7, figure 5 



Oliva gatunensis Toula, 1909, Jalirb. der K-K. Geol, Reicesanstaldt, 



vol. 58, p. 702, pi. 25, fig. 12. 

 Oliva reticularis gatunensis Brown and Pilsbry, 191 1, Proc. Acad. Nat. 



Sci. Phila., vol. 63, p. 348. 

 Oliva gatunensis Cossmann, 1913, Jour, de Conchyliologie, vol. 61, p. 



58, pi. 5, figs. 9-12. 



A common species at Gatun. The largest specimen in our 

 collection mieasures 28 mm. in length but Brown and Pilsbry men- 

 tion shells of an length of 35-38 mm. Oliva gatunensis, resem- 

 bles somewhat the brevirsoira of Gabb, but has a more even con- 

 ic spire and lacks the projecting nuclear tip. The sutures are 

 appressed. Brown and Pilsbry, place this shell as a variety of 

 the larger, recent Oliva reticularis Lamarck. 



Gatim Stage: Mt. Hope, C. Z. 

 Oliva sayana var. smmortlia Pilsbry and Brown Plate 7, figs. 6, 7 



Oliva sayana var. iniuiortua Pilsbry and Brown, 1917, Proc. Acad. 

 Nat. Sci. Phila., p. 33, pi. 5, fig. 6. 



The Oliva sayana Ravenel {Oliva liter ata oi most writers) 



