352 THE CHICAGO ACADEMY OF SCIENCES. 
Michigan. Beautiful and typical specimens may be collected 
at Joliet. 
145a. Valyata bicarinata normalis Walker. Unfigured. 
Valvata bicarinata normalis WALKER, The Nautilus, Vol. XV, p. 125, 
fig. 5, 1902. 
The shell in the variety differs from Jdzcarinata in being 
tricarinate, the middle carina very strong and placed on the 
periphery. The variety occurs at Joliet, Ill.,and at Miller’s, 
Ind. 
The curious larva case of Phryganea, named by Mr. Lea 
Valvata arentfera, is found in considerable numbers in various 
Fie. 182. 
Genitalia of PALUDINA VIVIPARA Linné. (Bronn, Klass. und Ord. 
der Weich., taf. LXXXVIII, Figs.5 (2), 6(¢). A, female; B, male; gal, 
albuminiparous gland; ov, ovaries; p, penis; rs, receptaculum seminis; t, 
testicles; ut, uterus; vd, vas deferens; vg, vagina; vs, seminal or genital 
bladder. 
parts of the region. The case is of exactly the same shape as 
that of a Valvata,and might be mistaken by an amateur for V. 
‘sincera. For a very interesting account of this larva case, see 
Thos. Bland, Ann. Lyc. N. H., Vol. VIII, p. 144. 
FAMILY VIVIPARID. 
Shell: Globular or conical, either banded or plain and 
with a greenish epidermis; aperture round; peristome con- 
tinuous, entire; operculum horny, annular, frequently with a 
spiral nucleus. 
Animal: With a large, simple foot, and short, simple ros- 
trum; tentacles short, the right one, in the male, modified to 
x 
; 
Te ot 
