PALEONTOLOGY ZORRITOS FORMATION 63 



rather of the Eocene Turritellas, confirmation of its strati- 

 graphic position in Peru must be forthcoming before it can 

 be taken seriously. The type specimen, beautifully pre- 

 served, and a striking object, occurs in Nelson's collection, 

 and was undoubtedly taken from a different locality. Inas- 

 much as the Zorritos formation is the only one exposed 

 within the area from which the Hopkins, and, presumably, 

 Nelson's fossils were taken, it is highly probable that 7\ 

 alturana occurs somewhere within the limits of that forma- 

 tion. T. andersoni Dickerson, 55 from the Tejon Eocene of 

 California, is the most closely related form, and excepting 

 its marked difference in size might be held by some to be 

 identical with T. alturana. Its sutural depression is by no 

 means as prominent as is that of alturana, but otherwise the 

 figure (magnified three times) given by Dickerson corres- 

 ponds exactly to the smaller specimens of alturana in the 

 Zorritos collections. 



It is also close to T. infragranulata Gabb, 56 from the Cali- 

 fornia Eocene, but lacks the granules of that species. T. 

 pachecocnsis Stanton 57 is similar, but has a much wider 

 sutural depression, and bears granules. Two species from 

 the Alabama Eocene, T. alabamiensis Whitfield 58 and T. 

 saffordi Gabb, 59 are similar, but much smaller and more 

 delicate. 



Horizon unknown. Loose block near mouth of Quebrada 

 Tijeritas. 



Turritella bifastigata Nelson 

 III Fig. i. 



Turritella bifastigata Nelson, Trans. Conn. Acad., vol. 2, p. 

 9, 1870. 



53 Univ. Cal. Bull. Geol., vol. 9, p. 501, pi. 42, hgs. 9, gb, 1916. 

 56 U. S. G. S. Ann. Rept. No. 17, p. 1044, pi. 66, fig. 3, 1896. 

 "Idem., p. 1043, pi. 66, figs. I, 2. 

 58 Bull. Amer. pal., vol. i, No. 4, p. 109, pi. n, fig. 6. 



59 Ibid., p. 109, pi. 11, fig. 7. 



