COLIMACEA. MOLLUSCA. HELIX. 173 



of brown ; tentacula smoky ; eyes black ; base of foot inky, tip 

 dirty flesh-color ; respiratory orifice surrounded by a dark circle ; 

 length about twice the diameter of the shell. 



Inhabits the sea-coast, and is common on the lower parts of 

 Cape Cod and Cape Ann. It is very abundant on Salt Island, 

 near Gloucester. It has been noticed in the region of Portland, 

 Maine, and along the banks of the St. Lawrence. 



This species, so abundant in Europe, and so well known in every 

 cabinet, has been undoubtedly imported to this continent, and has not 

 as yet made great advances into the interior. The specimens first 

 discovered by Dr. Binney were all of the plain, greenish-yellow va- 

 riety ; and, though he could not fail to perceive their affinity to the H. 

 hortensis, he thought he discovered differences enough to entitle them 

 to a specific distinction, and therefore described them under the name 

 H. suh-globosa. But numerous specimens have since been brought 

 from the same vicinity, bearing all the various zones of the European 

 specimens. His remarks on the manner in which the epiphragm, 

 which closes up the orifice in winter, is formed, are curious. Unlike 

 other American species, they are not found burrowing under stones 

 and decayed leaves, but on the ground, and crawling up the stems of 

 plants. 



The best authorities now regard the H. hortensis of authors as 

 merely a variety of H. nemordlis, Lin., with a white instead of a 

 dark lip. 



Helix tridenta'ta. 



Shell depressed, yellowish horn-colored ; whorls obliquely 

 wrinlcled ; aperture contracted, three-lobed, two teeth on the outer 

 lip, and a curved one on the pillar ; lip refiexed, white ; umbilicus 

 deep. 



Figure 115. 



State Coll., No. 103. Soc. Cab., No. 1019. 



Helix tridentata, Say ; Mck. Encyc, (Amer. ed.) iv. Fe'russac ; Hist, des Moll., 

 pi. 51, f. 3. Deshayes ; Encyc. Mith., Vers, ii. 213. Lam.; j]n. sans Vert., 

 viii. 115. Wood; Index, SuppL, pi. 7, f. 2. Binney ; Bost, Journ. JVat. Hist., 

 iii. pi. 22,f. 1. 



Shell flattened, slightly convex above and below, yellowish 

 horn-colored ; whorls four and a half to six, slightly convex, 



