SUCCINEA. 421 



Succinea avara, Say, Long's Exped., II. 260, PI. XV. Fig. 6 (1822); Binney's 



ed. 32, PI. LXXIV. Fig. 6. — Gould, Invertebrata, 196, Fig. 127 (1841). — 



Adams, Shells of Vermont, 156 (1842). — DeKay, N. Y. Moll., 54, PI. IV. 



Fig. 55 (1843). — Pfeiffer, Symbolae, II. 56; Mon. Hel. Viv., II. 525; in 



Chemnitz, ed. 2, 51, PI. V. Figs. 18 - 20 (1854). — Binney, Terr. Moll., II. 



74, PI. LXVII. c, Fig. 4. — W. G. Binney, Terr. Moll., IV. 35 ; L. & Fr.-W. 



Sh., I. 262 (1869). —Morse, Journ. Portl. Soc, I. 29, Fig. 75; PI. IX. Fig. 



76 (1864) ; An .: Nat., I. 607, Fig. 47 (1868). — Tryon, Am. Journ. Conch., 



II. 233 (1866). 

 Succinea Wardiana, Lea, Proc. Am. Philos. Soc, 1841, II. 31 ; Trans., IX. 3 ; 



Obs!, IV. 3 (1844). — Pfeiffer, Mon. Hel. Viv., II. 525. 

 Succinea vermeta, Say, teste Gould (see doubtful species, p. 430). — Tryon, Am. 



Journ. Conch., II. 233, PI. II. Fig. 10 (1866). 



From Fort Simpson, on Mackenzie River, to the Gulf of Mexico ; over all 

 the Eastern Province ; also in Colorado and New Mexico, of the Central 

 Province. 



Head dark ; foot flesh-colored, narrow. 



A larger form is also found. 



This shell at first sight appears to be the young of some of the larger species, 

 but it has as many whorls as any of them, though not attaining more than one 

 fourth part their size. It differs from all others in having a long and pointed 

 spire, and in its shorter aperture, which is only half as long as the shell. The 

 whorls do not expand so fast from the apex towards the aperture, and the last 

 whorl consequently forms a much smaller part of the whole volume of the shell. 

 One of its characters, but not entirely peculiar to it, is the loose manner in 

 which the whorls are united, the suture being in some instances so deep as 

 nearly to separate tbem. This variety was considered by Mr. Say to be a dis- 

 tinct species, and described by him under the name of Succinea vermeta. We 

 have carefully compared Succinea Wardiana, Lea, with the present species, but 

 cannot detect any difference. 



In the young shells the spire is not so prominent, and the periostraca is cov- 

 ered with numerous fine, hairy processes, as in some Helices, which accumulate 

 particles of dirt, which in this way sometimes coat over its entire surface. 

 The apex of the spire is often rosy. 



Found under stones and fragments of wood in moist places, and often on hill- 

 sides and other positions far removed from water. 



Allied to S. putris, var. ochracea, according to Mr. Gwynn Jeffreys (Ann. 

 Mag. Nat. Hist., 1872, 246). 



Jaw strongly arcuate, ends curved and pointed ; anterior surface smooth ; 

 concave margin simple, with a well-developed, acute median projection ; con- 

 vex margin waving. 



Lingual membrane (PI. X. Fig. K) with 21—1—21 teeth, with about 8 per- 

 fect laterals. Morse counted 19 — 1 — 19 teeth. 



