388 PROCEEDINGS OF THE ACADEMY OF [Juiie, 



of hills which reach about 5,500 feet elevation. On the northern 

 and northwestern slopes of one of these, about two miles east of the 

 town, we collected Sonorella, Holospira and some smaller shells. 

 Holospira is very abundant (over 1,500 collected by H. A. P.), 

 living in mellow earth under stones, in "nests" of from six to twenty 

 or more, usually standing vertically, apex up, and buried in earth 

 up to the summit. While the sculpture of this species is coarser 

 than that of typical H. cionella, yet there are some equally coarse 

 individuals of the latter. It is quite possible that H. cionella may 

 eventually be ranked as a subspecies of H ferrissi. 



In the debris of the San Pedro River above the S. P. R. R. bridge, 

 near Benson, Arizona, we found three specimens representing as 

 many races of Holospira. One is the upper half of a slowly tapering 

 species, evidently new. The others are probably races of H. ferrissi. 

 One specimen has the appearance of a small H. f. fossor. It has the 

 same sculpture, a low axial lamella, and measures, length 7.6, diam. 

 3.1 mm., 9f whorls. 



The other shell resembles H. ferrissi in having three internal 

 lamellae, the superior and axial lamellae being strongly developed. 

 .The ribbing is as fine as in the most finely ribbed ferrissi — decidedly 

 finer than in fossor. The form is more slender than in ferrissi. 

 This shell apparently represents another subspecies or local race 

 of H. ferrissi. As it may have drifted a long distance, it had better 

 be left nameless until found in its natural habitat. 

 Holospira ferrissi sanctaecrucis n. subsp. PI. XV, fig. 7. 



The shell is similar to the most slender and fine-ribbed examples 

 of H. ferrissi in form and sculpture, except that the apical whorls 

 are more mucronate. The three internal lamellae are lateral in posi- 

 tion, strongly developed, especially the superior one, w^iich is a half- 

 whorl long. 



Length 8.5, diam. 3.2 mm.; whorls 11|. 



Valley of the Santa Cruz River, above Tucson, Arizona. Type 

 No. 112,239, A. N. S. P., found in flood debris of the river a short 

 distance above the Congress St. bridge, Tucson. 



This is some distance west of any other record of Holospira in the 

 United States. In Mexico the genus extends to the Gulf of Cali- 

 fornia. The lamellae are much stronger than in any of the lot of 

 H. ferrissi which we have opened. 



Although there cannot be much doubt that this species inhabits 

 some limestone hill not far from the river, we failed to find it in the 

 quite limited time we spent in the neighborhood. It may have 



