62 STROBILOPS. 



up in a long time. I am naming it in honor of my friend 

 Dr. W. Wenz of Frankfurt a.M., whose work on the Tertiary 

 Strobilops of Europe has contributed materially to our under- 

 standing of this ancient group. 



Section Nesostrobilops, n. sect. 



Strobilops with conic spire of few (4i/^) whorls, the parietal 

 lamellae without nodes ; no interparietal lamella and no colum- 

 ellar. Basal folds 3 or 4. Type S. helleri. 



The only species known of this insular group resembles Dis- 

 costrohilops in having no colum.ellar lamella, fewer whorls 

 than in other Strobilops, and with the internal barrier less 

 deeply immersed, so that the folds can be seen in an oblique 

 view in the aperture. Also, there are no nodes on the parietal 

 lamella, though it is microscopically roughened. 



10. Strobilops helleri (Dall). PL 16, figs. 1, la, 2, 2a. 



See this vol., p. 41, where the type was described and 

 figured. The California Academy Expedition collected speci- 

 mens at the following places: Albemarle Island near Cowley 

 Mountain on moist ground at 350 to 500 feet ; on Narborough 

 in grass and bushes at the rim of the crater at 4000 feet; and 

 on James Island, in moist grass and bushes at 1800 to 2000 

 feet (W. H. Ochsner), in Dall and Ochsner, Proc. Cal. Acad. 

 Sci. (4), vol. 17, p. 176, 1928. 



Tlirough the courtesy of Dr. G. D. Hanna of the California 

 Academy of Sciences I have obtained specimens of Strobilops 

 from Narborough and James Islands. The Narborough shell 

 (pi. 16, figs. 1, la) is barely mature, being still somewhat 

 transparent, with the lip somewhat expanded, but little thick- 

 ened. The base is finely striate, not ribbed, but ribs reappear 

 within the umbilicus. The peripheral carina is not distinctly 

 bordered above and below, as in the type specimen from 

 southern Albemarle. There are four basal folds, the fourth 

 (nearest the periphery) being longest, the second next, the 

 first and third shorter and about equal in length, though the 

 first is stouter (PL 16, fig. 1). The parietal lamella extends 

 inward very little beyond the basal armature; its inner half 



