360 North American Species of Zonites, etc. 
Dr. Lewis, and find them to be rather a variety of gularis—one 
of the many curious forms of that variable species. The internal 
tooth-like processes, strongly curved one towards the other, form 
almost an arched space. On pl. XV, fig. C, will be found a 
ae of this form. Dr. Lewis’s specimens were from Munroe 
Co., Tenn. (Miss Law). I have also received it from Roan 
Mountain, N. C. (Mrs. G. Andrews). 
Webennophorus, ——. 
From Dr. W. Newcomb I have received a slug which, from its 
outward characters, Jaw and lingual membrane, surely is a spe- 
cles of Tebennophorus. It is mentioned here, as the locality is 
new for the genus—Brazil, 300 miles up the river from Para. 
Mesodon dentifera, Binn. 
Vermont. 
On pl. XIV, fig. G, I have figured the genitalia of this species, 
hitherto unknown. 
The genital bladder (g. 0.) is small, oval, on a short duct 
which is greatly swollen at a short distance below the bladder: 
the penis-sac (p. s.) is long, stout and contracted, at a short dis- 
tance below its blunt end: the retractor is inserted in the vas 
deferens at about the middle of its length. 
In another individual, the construction of the penis-sac was 
not so well developed. 
Mesodon Andrewsi, n. sp. 
At Roan Mountain, Mitchell Co., N. C., Mrs. Andrews col- 
lected numerous specimens of a Mesodon which cannot be referred 
to any known species. 
Shell imperforate, globose, very thin, with delicate wrinkles of growth 
and microscopic revolving strive ; horn color ; spire elevated, conic, apex 
obtuse ; whorls six, convex, the last greatly swollen; peristome white, 
thickened, slightly reflected, ends separated, the columellar one expanded. 
Greater diameter 25 mill., lesser 20 ; height 14 (Plate XV, Fig. L). 
The absence of |-mestone on Roan Mountain accounts for the 
extreme thinness of the shell. 
It can scarcely be said to resemble closely any known species 
