182 LAND AND FRESH- WATER SHELLS OF N. A. [PART L 



gradually becoming modified into uncini with irregular and ob- 

 tusely rounded denticles. 



Fig. 320. 



Lingual dentition of Helix hortensis. [Morse.] 



The Helix nemoralis of Europe, distinguished readily from 

 H. hortensis by its black peristome, but by many considered 

 identical, does not appear to have been introduced from Europe 

 into the New England States or British Provinces. In 1857 I 

 imported some hundred living specimens from near Sheffield, 

 England, and freed them in my garden, in Burlington, New 



Jersey. They have thriven well 

 Fig. 321. a,nd increased with great ra- 



pidity, so that now (1865) the 

 whole town is full of them. They 

 retain the habit of the species of 

 climbing hedges and trees, not 

 Meiix nemoralis. remaining concealed under de- 



caying leaves, logs, &c., like the 

 American Helices. Fig. 321 is drawn from Burlington speci- 

 mens. The experiment of introducing the Helix nemoralis is 

 interesting, as showing the adaptability of the species to a new 

 climate. Other species, among them H. lajncida from England, 

 and Stenogyra decollala from Charleston, S. C, placed in my 

 garden at the same time, disappeared at once. 



The jaw of a Burlington specimen is very strongly arched, 

 with four stout ribs on its anterior surface, denticulating each 

 margin. 



Locality. 



Massachusetts. 



lis. \n Casco Bay, Me. 



Halifax, N. S. 



House Is., Manchester, 



Mass., lis. [Mass. 



Ludlowville, Cayng-a L. 



From whom received. 



W. Stimpson. 



Villius. 



W. G. Binney. 



Vf . Stimpson. 



Mrs. H. W. Parker. 



Remarks. 



(H. subglvbosa.) 



