406 THE CHICAGO ACADEMY OF SCIENCES. 
lus rather heavy in some specimens in which case making a continuous 
aperture; axis very slightly twisted; columella with a well marked 
fold, more strikingly developed in immature than in very old speci- 
mens, and frequently indicated only by a tubercle-like swelling. 
Length. Width. Aperture length. Width. 
19.00 10.00 10.10 5.00 mill. Type. 
16.50 9.50 9.10 4:80) Fe 
14.50 8.50 8.50 A00G— © 
14.00 7.50 7.50 3.40 fy 
12.50 7.50 8.00 SAO} = e 
Types: Chicago Academy of Sciences, five specimens, No. 23806. 
Cotypes, collections of Academy of Natural Sciences, Philadelphia 
and A. A. Hinkley. 
Type Locariry: Jackson Lake, drained by the south fork of the 
Snake River, Wyoming. 
ANIMAL, JAW, RApuULA and GENITALIA: Unknown. 
RanGE: Wyoming and Idaho. A species of the Boreal (Canadian) 
‘fe zone and of the Columbian region. 
RECORDS. 
IpAHO: Snake River (Dall). 
WyominG: Jacksons Lake, drained by the south fork of the Snake River; 
Phelps Lake, eight miles south of Jacksons Lake (H. O. Hinkley; A. A. Hink- 
ley). 
GEOLOGICAL RANGE: Unknown. 
Ecotocy: Not recorded. 
REMARKS: This species was received from Mr. A. A. Hinkley of 
DuBois, Illinois, under the name of binneyi. Comparison with Tryon’s 
types showed at once that it was not that species which is larger, of 
a different color and with a differently shaped shell, inner lip, umbili- 
cus, etc. It approaches gabbii Tryon, but the aperture is more regularly 
clongate-ovate, the whorls are rounder, the inner lip is broader, there is 
an umbilical chink and the whole shell is more fusiform. Comparison 
has been made with Tryon’s types and with a set in the Chicago Acad- 
emy of Sciences, from the original lot received from Tryon. It has 
some resemblance to catascopium, but the columella is quite dissimi- 
lar, there is an umbilical chink, the color of shell and aperture is differ- 
ent, and the aperture is differently shaped. Jacksonensis has a super- 
ficial resemblance to swmassi but differs in being shorter and wider, 
smaller (usually) and with a very different columella (compare the 
figures of these species on plates XLI and XLII). The reference by 
the writer in the Nautilus to Binney’s figures of shells from Grind- 
stone Creek was an error, as these figures refer to apicnia. Jackson- 
