FAUNA OF ORTHAULAX PUGNAX ZONE. 2S 



CEPOLIS (PLAGIOPTYCHA) INSTRUMOSA Dall. 



Plate 2, figs. 6, 15. 



Helix (Jeanneretia) instrumosa Dall, Trans. Wagner Inst., vol. 3, pt. 1, p. 

 9, pi. 1, figs. 7, 8&, Aug., 1890. 



Tampa silex beds, collected by Dall. U. S. Nat. Mus. No. 111945. 



CEPOLIS (PLAGIOPTYCHA) DIREPTA Dall. 

 Plate 2. figs. 12, 14. 



Helix (Jeanneretia) dlrepta Dall, Trans. Wagner Inst., vol. 3, pt. 1, p. 10, 

 pi. 1, figs. 7a, Ih, Aug., 1890; pt. 5, p. 1195, pi. 39, figs. 4, 5, Nov., 1900. 



Tampa silex beds, rare. Dall and Burns. U. S. Nat. Mus. No. 

 130354. 



Tribe EPIPHALLOGONA. 



Genus PLEURODONTE Fischer de Waldheim. 



Pleuroilonte F. de Waldheim, Tab. Syu. Zoogn., p. 129, ISOS. — Pilsbrt, 

 Man. Conch., vol. 9, 1894, p. 84. Type, Helix sinuata Gmelin, 

 Jamaica, West Indies. 



A few of the larger species of silex bed Helicidre show a more or 

 less granulate surface, especially C. haruspica Dall, and this not 

 being found in Cepolis^ has led Doctor Pilsbry to suggest their 

 affinity to Pleurodonte of which they may represent the progenital 

 type. 



I have felt some little hesitation in referring species to this genus, 

 on account of the fact that the pressure of sand grains on the surface 

 of the pseudomorph sometimes gives the effect of finely granulate 

 sculpture, but have finally done so provisionally. 



PLEURODONTE HARUSPICA Dall. 



Plate 1, figs. 12, 13, 14 ; plate 2, fig. 11. 



Helix {Jeanneretia) haruspica Dall, Trans. Wagner Inst., vol. 3, pt. 1, 

 p. 11, pi. 1, figs. 7c, Id, Aug., 1890. 



Tampa silex beds, at Ballast Point, Tampa Bay, Florida. Abun- 

 dant but usually defective. Collected by Shepard, Post, and Dall, 

 U. S. Nat. Mus. No. 165005. 



This appears to be the largest species of the formation and, though 

 smaller than most of the recent species, by its carinated periphery 

 indicates its alliance with them. In perfect specimens the axis is 

 hermetically sealed in the adult ; not even a depression occurs in the 

 umbilical region, but the young are perforate. 



