172 INVERTEBRATA OF MASSACHUSETTS. 



sometimes grooved, its exterior yellowish ; at the inner side, on 

 the last whorl, is a white, tooth-like tubercle, placed obliquely ; 

 umbilicus exhibiting only one volution, and partially covered by 

 the reflected lip. Diameter about three fourths of an inch. 



Animal of a dirty yellowish-color, with a greyish hue in some 

 individuals ; tentacula darker ; eyes black ; base of the foot dirty 

 white ; length equal to twice the diameter of the shell. 



Found in nearly all parts of this State, but by no means com- 

 mon. It is numerous in all the Southern and Western States. 



This is a plain but pretty shell, bearing a great resemblance to H. 

 alholabris, yet readily distinguished from it. It is a smaller shell, 

 more globose ; its aperture is more oblique, and the partially closed 

 umbilicus and tooth on the inner lij) are specially characteristic. It 

 varies considerably in its size, and in the degree of its convexity. 

 The umbilicus is sometimes entirely closed ; and in immature shells 

 the tooth is generally wanting. It is occasionally found reversed. 



Helix horte'nsis. 



Shell sub-globose, thin, smooth, greenish-yelloiv, or variously 

 handed with brown; lip rejiexed, white, thickened within; umbil- 

 icus closed. 



State Coll., No. 102. Soc. Cab., No. 994 to 996. 1062. 



Helix hortensis, Muller; Verm., 52, No. 247. Born; Mus.t.ld, f. 18, 19. 



Chemn.; Conch., ix. t. 133, f. 119!) to 1201. Draparnaud : Moll., pi. 6, f. 6. 



Fe'rcssac ; Hist. desMolL, pi. 35 and 3G. Lam.; Jin. sans Vert., viii.55, where 



references to numerous other works may be seen. 

 Helix sub-globosa, Binney ; Bust. Journ. JVat. Hist., i. 485, pi. 17. Monogr., pi. 6. 



Shell sub-globular, thin, smooth, and shining ; whorls four or 

 five, convex, with apparent lines of growth ; suture distinct ; ter- 

 mination of the outer whorl declining ; aperture rounded, slightly 

 contracted at the base by the thickening and inflection of the lip ; 

 lip slightly reflected, white, thickened within ; base somewhat 

 convex, umbilicus covered ; general color greenish-yellow, more 

 or less dark ; sometimes plain, but generally variously banded 

 with dark reddish-brown. Diameter about three fourths of an 

 inch. 



The animal has the head and neck blackish, with a slight tinge 



