HELIX. 201 



46. HELIX PUSTULA, FeRUSSAC. 

 Plate XXXIX. Figoee 3. 



H. testa parva, planorboidea, cornea, strlatula ; spira 

 planulata, anfractibus quinis, convexis, arete volutatis, sutura 

 bene discretis, ultimo subangiitato ; apertura coarctata, lu- 

 nata, peristomate albo, reflexo, bilobato, marginibus dente 

 obliquo linguiformi junctis; infra conve.xa, late umbilicata. 



SYNONYMS AND REFERENCES. 



Helix piistula, Ferussac, Hist. Nat. des Moll. pi. 50, f. 1. 



Pfeiffee, Symhote, III. p. 81. Monog. Helic. Viv. I. 422. 

 Chemnitz, 2d. ed. t. 65, f. 18-20. 



DESCRIPTION. 



Shell small, planorboid, pale rufous or horn-colored, 

 delicately striated. The spire is flat, has five closely 

 revolving, rounded whorls, separated by a deep suture, 

 the outermost obtusely angular at its upper limit ; beneath 

 convexly rounded into a large umbilicus, one-third the 

 breadth of the base, and exhibiting the other Tvhorls 

 within, and with a constriction behind the lip. Aperture 

 narrow, crescentic, the Mp somewhat broadly reflected, 

 white, its inner margin divided by a median fissure, from 

 which it is narrowed each way, forming two dentiform 

 lobes ; on the columella is an erect lamella proceeding 

 obliquely from below, its upper extremity being annexed 

 to the upper extremity of the lip by a filiform callus. 



Diameter one-fifth, axis one-tenth of an inch. 



Geographical Distribution. Foimd at Darien, and 

 in Lee county, Georgia, and in Florida. 

 vol. II. 51 



