426 PROCEEDINGS OF THE ACADEMY OF [May, 



intermediate between tlie typical form characteristic of the higher 

 altitudes of Eoan and INIitchell and subsp. altivaga, which similarly 

 occupies the summits of the Smoky mountains. In texture, sculp- 

 ture, color and character of the peristome it is nearer to altivaga, 

 but in shape is more like the typical andreivsce. On the whole, 

 however, it is more nearly related to the former. It may be char- 

 acterized as typical in shape, but larger, with a stronger, thicker 

 shell, closely and regularly striate, lighter in color being usually 

 with a strong yellowish tinge, frequently pale green, and occa- 

 sionally tinged with red ; the lip is decidedly different from the 

 typical andrewsce, being broader and flatly reflected ; in many cases 

 the reflected portion is decidedly convex, bemg rolled back so that 

 the center of the face of the peristome projects beyond the outer 

 edge. Compared with var. altivaga it is decidedly less globose, 

 being wider in proportion to its height. The aperture also is propor- 

 tionately wider than in altivaga. 



It was first met with on Bluff mountain at Baker's, and ranged 

 from there to the summit. Of eight specimens, the largest was 

 30J mm. in diameter, the smallest 26^, average 28| mm. The 

 largest example compared with a Thunderhead specimen of the 

 same diameter, 30 J mm. , will show the following difference in height 

 and breadth which is characteristic of the race : 



Dlam. Total Alt. Alt. of Axis. 



Bluff mountain {intermedia), . . 30|- 22 15J 



Thunderhead (altivaga), ... 30^ 22 16J 



Potato Top (4,000 feet), six specimens, largest 30 x 20|-, 

 smallest 26^ x 20, average 28|^ mm. 



Vance's branch, North fork of the Swauauoa river, two speci- 

 mens, rather heavier than usual, 26 x 20 and 26^ x 20 mm. 



Bee Tree creek. Craggy mountains (alt. 3,500 feet), three 

 specimens similar to those from Vance's branch. Shells as thick 

 as those of subsp. normalis. These specimens are very close to 

 subsp. altivaga, and have the notch at the upper end of the peris- 

 tome as in that form. They measure 25, 27 and 27^ mm. in 

 diameter. One of them is decidedly reddish horn-colored. On 

 Craggy, Fei'riss found intermedia all along from 4,500 to 6,000 

 feet. He remarks that its habits are similar to those of Polygyra 

 exoleta and solitary. 



Two specimens from Balsam Gap, Ivy river (alt. 3,500 feet). 



