SUCCINEA. 427 



Succinca injltxta, Lka, Trans. Am. Phil. So(^, IX. 5 ; Obs., IV. 5 (1844) ; Pror:., 

 II. 31 (1S41). — rKKiFFKit, Mon. H(*I. Viv., II. 526; in Chemnitz, «(1. 2, 49, 

 PI. V. Figs. 9-11 (1854). — W. G. Binnky, Terr. Moll., IV. 34, PI. LXXX. 

 Fig. 11. — TiiYON, Am. Journ. Conch., II. 230 (18G6). 



Succinca unicohr, Tryon, Am. Journ. Conch., II. 230, PI. II. Fig. 3 (1866). 



It is a strictly Southern Region species, observed us yet only in Florida and 

 Georgia. 



Whitish ; eyes, tentacula, and a line passing from the eyes disappearing 

 under the shell, black ; a gamboge-colored vitta is visible through that part of 

 the shell wliich is opposed to the mouth. At St. Augustine I found specimens 

 copulating in December. 



Jaw as usual ; no anterior ribs. 



The lingual membrane (PI. X. Fig. O) has 18—1—18 teeth, with about 10 

 perfect laterals. Morse gives 50 rows of 30 — 1— £0 teeth. The central tooth 

 has a peculiarly narrow base of attachment, and a very greatly developed me- 

 dian cusp, the side cusps being subobsolete. 



Genitalia as in S. obliqua (q. v.). 



Succinea Ha-wkinsi, Baird. 



Shell elongate-obovate, thin, pellucid, shining, undulately striated, pinkish, 

 within pearh' ; spire acute ; whorls 4, convex, the last 

 equalling two thirds the shell's length ; suture impressed ; Fig. 304. 



aperture oval, effuse below. Length |, lat. ^ inch. 



Hab. Lake Osoyoos, British Columbia. (Brit. Mus.) 



This shell is of an elegant form, and of a pinkish color, 

 with the interior of a pearly lustre. It is smooth and 

 shining, but marked with waved striae of lines of growth. 

 It resembles very much in figure the Succinea Pfeifferi of 

 Europe, but is of a still more elegant shape and of a 

 brighter hue. 



I have named it after Lieutenant-Colonel Hawkins, R. E., Commissioner of 

 the British North American Boundary Commission. (Baird.) 



Sticcinea Haivkinsii, Baird, Proc. Zool. Soc, 1863, 68, in Lord's Nat. in Van- 

 couver's Island, II. 362 (1866). — Bland, Ann. N. Y. Lye, VIII. 168, Fig. 16 

 (1865). —Tryon, Amer. Journ. Conch., II. 240 (1866). —W. G. Binney, L. 

 & Fr.-W. Sh., I. 268 (1869). 



A species of the Northern Region, confined to British Columbia, as far as 

 now known. 



Animal unknown. 



Fig. 304 is copied from the original figure. 



Succinea rusticana, Gould. 



Shell elongate, ovate-conical, rather large, thin, and fragile, pale greenish 

 horn-color, surface rude and without lustre, coarsely and irregularly marked by 



