218 THE CHICAGO ACADEMY OF SCIENCES. 



part, and is joined at its summit by the vas deferens; the 

 retractor muscle is inserted into the penis sac a short distance 

 from its summit; the genital bladder is large and globular; its 

 duct is nearly as long as the oviduct, and is narrow; the vagina 

 is moderately long and muscular; the cloaca is short.* 

 Distribution : World-wide. 



KEY TO SPECIES OF SUCCINEA. 



A. Spire short, aperture occupying the greater part of the shell. 



a. Aperture wide, oblique ovalis 



b. Aperture long, narrow, straight retusa 



B. Spire long, aperture occupying a little over half of the shell. . . .avara 



84. Succinea ovalis Say, pi. xxx, figs. 22, 23. 



Succinea ovalis SAY, Journ. Phil. Acad., Vol. I, p. 15, 1817. 



Succinea obliqua SAY, Long's Expedition, Vol. II, p. 260, pi. xv, fig. 7, 



1824. 



Succinea totteniana LEA, Proc. Amer. Phil. Soc., Vol. II, p. 32, 1841. 

 (Variety.) 



Shell: Large (for the genus), thin, fragile, ovately-oblique, 

 pellucid; surface shining, marked by distinct lines of growth, 

 sometimes raised in ridges; color yellowish green or amber, 

 sometimes very light, at others very dark; whorls three, rapidly 

 enlarging, the last being more than twice the length of the 

 others combined, very oblique and much expanded; spire 

 short, blunt; sutures well impressed; aperture obliquely ovate, 

 very large, occupying more than two-thirds of the entire shell; 

 columella thin, narrow, its margin slightly glazed with testa- 

 ceous matter; peristome thin, blunted, the terminations con- 

 nected by a thin callus; the shell is covered with a very fine 

 periostracum. 



Length, 22.00; diam., 12.50; aper. length, 15.50; diam., 9.50 mill. (10451.) 

 22.00; " 13.00; " " 16.00; " 9.75 " (10451.) 

 20.00; " 12.00; " " 14.00; " 9.00 " (10449.) 

 17.50; " 11.00; " " 12.50; " 9.00 " (10442.) 



Animal: With a wide foot, truncate before, rounded be- 

 hind; color in general yellowish or saffron, with seven distinct 

 black lines on the anterior part, one in the center of the head, 

 one on the dorsal surface of each eye-peduncle, one on each 

 side of the neck and one on each side of the foot; the mantle 

 is grayish in color; tentacles white, small, inconspicuous; eye- 

 peduncles rather short, thick, blunt, the eyes placed as usual 

 at the tips; there is a deep furrow on each side, commencing 



* Man. Amer. Land Shells, p. 343. The author is also indebted to Mr. Binney for much 

 or most of the information used under the generic description of Succinea. 



