380 



PROCEEDINGS OF THE ACADEMY OF 



[June, 



Station 21, hillside, eastern slope of second ravine from granitic 

 spur, up to about 600 feet above bed of ravine. The shells are 

 variable, as would be expected in a lot gathered over a considerable 

 area, having 35 to 50 ribs on the penultimate whorl. Out of 1 1 opened, 

 one has 3 lamellse, ten have two, superior and axial. (PI. XIV, fig. 6.) 



Station 22, in the bed of the same ravine. Shells having about 56 

 ribs on penultimate whorl. Eight opened have 3 very strong lamellse. 



Station 23. Between Stations 21 and 2, near top. Like the 

 preceding, lamellae 2 or 3. 



Fig. 2. — Sketch to show positions of collecting stations west of the spur in Tweed 

 Canyon. Contour interval about 400 ft. The granitic dyke about 50 

 yards wide between Stations 17 and 18 separates colonies of H. c. cochisei 

 (below) from those of H. danielsi (above). 



Station 27. Rather large, length 11 mm. with 12 whorls and 36 

 ribs on the penultimate whorl to 13 mm. long, with 13^ whorls and 

 28 ribs. (PL XIV, figs. 8 to 86.) This station is in a gulch on the 

 south side of Tweed Canyon, the nearest approach to the area of 

 H. miUestriata. It shows no approach to that species in sculpture, 

 which is coarser than in most cochisei. Some of the ribs were hollow 

 and are broken down, as in H. danielsi. This condition is also seen 

 to a less degree in some specimens of cochisei from the type locality. 



Holospira miUestriata n. sp. PI. XV, figs. 3 to 5c. 



The shell is shortly rimate, tilleul-buff, composed of about 11 J 

 convex whorls, of which the last 5 form the cylindrical, those pre- 

 ceding the conical portion. Embryonic 2 whorls smooth, somewhat 

 nipple-like, the second whorl becoming very narrow. Succeeding 



