1915.] NATURAL SCIENCES OF PHILADELPHIA. 333 



Genitalia similar to 0. hachetana, except that the lower third of 

 the duct of the spermatheca is more enlarged. Length of penis 

 5 mm.; epiphallus 5.5 mm.; spermatheca and duct 9 mm. (fig. 4 B). 



Hacheta Grande Mts. at Station 3, on ledges of high cliffs opposite 

 the mouth of Sheridan Canyon, under stones, Pilsbry and Daniels, 

 August 21, 1910. Cotypes. No. 112,276, A. N. S. P. Also at 

 Station 1, Teocalli Butte. 



0. ferrissi has much the appearance of the Chiricahuan 0. barbata 

 Pils., but this resemblance is superficial. When denuded of the 

 cuticular fringes, the two are quite different, the Chiricahuan specie? 

 being much smoother, without the strong spiral ridges of 0. ferrissi. 

 Moreover, the sculpture of the embryonic shell is different. The 

 shape of penis and epiphallus in 0. ferrissi is like 0. chiricahuana 

 and 0. clappi, both organs being enlarged distally, while in 0. barbata 

 the lower half of the penis is enlarged, the distal portion slender. 



In well-developed shells the last whorl scarcely descends anteriorly, 

 the upper margin of the lip being inserted on the peripheral carina. 

 In some of the smaller adults, diam. 13 mm., the last whorl is bent 

 downwards; the upper and columellar margins of the lip converge 

 and are connected by a raised parietal lamina, the mouth having a 

 somewhat triangular contour. These are to be regarded as decadent 

 (gerontic) individuals. 



At Station 1, Teocalli Butte, the shells are all convex above, with 

 a noticeably smaller umbilicus. The largest measures, alt. 7.8, 

 cliam. 15 mm., with 5 whorls (PI. VI, fig. 46). This small colony is 

 probably extinct or nearly so, as no living shells were found. 



Our Station 3 is on ledges of high clifTs facing the mouth of Sheridan 

 Canyon, and especially on a bench about half-way up. Here Ferriss's 

 Oreohelix lives on an almost inaccessible cliff looking out over the 

 mesa into Mexico. There is little vegetation on the ledges. On 

 the talus slope below the cliff there is a growth of dwarf oak about 

 knee-high, charming big wild roses of a species which we saw nowhere 

 else, Cylindropuntia, Opuntia, hisnagsis, etc. On top, above the cliffs, 

 the Fouquieria, sotol, mescal society is found. The Oreohelix colony 

 is of small extent; the ledges where they were observed living are 

 probably not over a couple of square rods in area, with perhaps an 

 equal area on the talus below the cliffs, where dead shells were found. 

 These estimates are from memory, as I neglected to note the figures 

 at the time. 



The locality on the east side of Teocalli Butte is more restricted, 

 ;and if possible more arid. 



