PALEONTOLOGY ZORRITOS FORMATION 163 



Siliquaria caribea Holmes, Post-Pleic. Fos. S.C., p. 54, pi. 8, fig. 

 14, 1858. 



Siliquaria carolinensis Conrad (ex parte) Proc. Ac. Nat. Sc. Phil. 

 for 1862, p. 571, 1863. 



Solecurtus sp. ind. Nelson, Trans. Conn. Acad., vol. 2, p. 200, 

 1870. 



Solecurtus angulatus Sow. Conch. Icon. Solecurtus, p. 8, fig. 23, 

 1874- 



Solecurtus centralis Sow. Conch. Icon., fig. 18, 1874, (not Say). 



Tagelus gibbus Dall, Proc. Bost. Soc. Nat. Hist., vol. 13, p. 251, 

 1870; Trans. Wag. Inst., vol. 3, pt. 5, p. 983, 1900. 



Two posterior fragments on complete casts of this form 

 occur in Nelson's collection. Comparison with typical speci- 

 mens of T. gibbus shows no difference in any detail. Known 

 occurrences of T. gibbus point to its first occurrence in the 

 Yorktown Miocene, and its occurrence in Peru in strata of 

 greater age is of interest. Although the lack of exact 

 locality labels for Nelson's forms lessens the assurance with 

 which they might be taken to come from the Zorritos 

 formation, the absence in the vicinity of Zorritos of beds 

 younger than the Zorritos formation makes rather strong 

 the probability that they were collected from those beds. 



Superfamily 

 Family SOLENIDAE 

 Genus SOLECURTUS (Blainville) 



Subgenus PHARELLA Gray 



Solecurtus (Pharella) planifolliculus n. sp. 



PLATE X Fig. 7. 



Shell small, long, thin and very fragile. Anterior and 

 posterior margins subequally rounded; dorsal margin nearly 

 straight on either side of the beaks, forming an angle of 

 about 1 60 ; ventral margin nearly straight, apparently 

 slightly emarginate. Beaks very nearly central in position. 



