SUCCINEA. 



2(^9 



SllCCiliea rusticaiia, Godld. — Shell elongate, ovate conical, rather 



large, thin and fragile, pale greenish horn-color, surface rude and without 



lustre, coarsely and irregularly marked by the lines of 



growth ; spire acute, of three or more moderately con- Fig. 4S3. 



vex whirls, separated hy a well-impressed suture, tlie 



last whirl large and long, narrowing towards the base ; 



body portion of the face of the shell moderately large ; 



aperture ovate, three-fourths the length of the shell ; 



fold of the columella distinct. Length of axis 12^^, 



breadth 6\ mill. Succinea mstioma. 



Succinea rusticana, Gould, Proc. Bost. Soc. Nat. Hist. 



IT, 187 (Dec. 1846) ; Mollusca of Expl. Exped, 28, f. 29 (1852).— 

 Pfeikfer, Mon. Hel. Viv. II, .523.— W. G. Binney, Terr. Moll. IV, 6, 

 pi. Ixxix, f. 14.— Tryox, Am. Journ. Conch. II, 263, pi. ii, f. 19 (1866). 



Oregon to Tulare Valley, California. 

 For a figure of the animal, see page 256. 



Succinea nilttalliana, Lea. — Shell lanceolate-ovate, thin and 

 fragile, of a dull horn-color, somewhat rudely undulated by the lines of 

 growth ; composed of about three tumid whirls, forming a conical spire, 

 the last whirl constituting nearly the whole shell ; suture 

 well marked ; aperture nearly two-thirds the length of the 

 shell, ovate, broadly rounded in front, the posterior angle 

 being also somewhat rounded by the abrupt curvature of the 

 peristome ; columella very gently curved, the region being 

 somewhat gibbous ; no fold on the columella, but in the 

 region of the spire it is slightly sinuous. Length 13, of aper- 

 ture 10 mill. 



Fia. 484. 



Snrrinei 

 nuttaUiana. 



Succinea nuttaUiana, Lea, Proc. Am. Phil. Soc. II, 32 (1841) ; Trans, 

 IX, 4; Obs. IV, 4 (1844).— Pfeiffer, Mon. Hel. Viv. II, 523.— 

 Binney, Terr. Moll. II, 81, pi. Ixvii, a, f. 4.— W. G. Binney, Terr. 

 Moll. IV, 6.— Tryon, Am. Journ. Conch. II, 236, pi. ii, f. 26 (1866). 



Oregon and California. 



