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1918.] NATURAL SCIENCES OF PHILADELPHIA. 297 
Alt. 13.3, diam. 22.3 mm.; 5 whorls. 
“14 PA D8 ‘“« ~seareely 5 whorls. 
cee 6) agro 8.’ “Swhorls: 
Santa Catalina Mountains at Station 17, bluffs near Mud Springs, 
on Pine Canyon. 
The last whorl descends more than in S. marmorarius, the aperture 
is more oblique, and the color of adults is paler.’ The immature 
shells have more of a cinnamon tint than the adults. 
The spiral lines mentioned in the description are usually very 
faint, often scarcely discernible, but in the largest example they are 
quite distinct. The umbilicus sometimes varies to somewhat 
smaller than in the type specimen. 
Mud Springs, on Pine Canyon, a branch of Sabino above Sabino 
Basin, is a walled hole in the mud. It is on the trail from Sabino 
Basin to Soldier’s Camp, the elevation about 7,000 ft. It is in the 
pine zone. The Sonorella was found in the first rocks east of the 
spring along the trail. Also at the foot of a high cliff, in stratified 
‘“norphyry,” in a ravine heavily wooded with cypress (Cupressus 
arizonica), about a mile southeast of the springs. 
Sonorella marmorarius imula n. subsp. PI. III, figs. 7, 7a. 
At. Stations 17 and 19 (1917), on a limestone hill 6 miles west of 
Brush Corral Ranger Station, north of Alder Springs, in the northern: 
foothills of the Catalinas, many specimens were taken, chiefly dead, 
differing from typical marmorarius by the somewhat darker color, 
and by having about a half of a whorl more in examples of similar 
diameter. 
Alt. 26.5, diam. 15 mm.; 53 whorls. 
Highty-five specimens from Station 19, all of the adults collected, 
measure as follows: 
isms ia MAN pees sd Sb ..-5 Do ow AeA ee 22.0, 22.9 23° 23.1 23,2 
Number of specimens... 1 1 1 3 if 3 il 3 
ism 10) mm... ae s): 23.3 238.4 23.5 23.6 23.7 23.9 24 24.1 
Number of specimens... 2 3 2 2 3 1 4 2 
Pima ON MM. SS 24.2 24.3 24.4 24.5 24.6 24.7 24.8 24.9 
Number of specimens... 6 i 4 5 3 2 3 
Diam mm mms. 2. 2b .. Dy A251 25.35. 204. 20-05 20,00220.0 26 
Number of specimens... 4 2 2 meter 1 2 1 
isnt MTN. sb ee 26.2 26.3 26.4 26:5 
Number of specimens... 1 1 1 1 
