HELIX. 61 



I have separated the synonymy of these varieties in 

 such a way as to show the opinion of various authors on 

 them. For my own part, I cannot consider them as dis- 

 tinct species. Mighels (Shells of Maine) considers/rater- 

 na and monddon distinct. 



It has also been noticed in Washington Co. Texas, 

 (Moore). 



HELIX STEXOTREMA FERUSSAC vol. ii. p. 151, pi. xlii. fig. 5. 



Helix Stenotrema PFEIFFER, Symb. ii. 39, (excl. ? pustula.) 



REEVE, No. 720, (1852). 

 Helix hirsuta {3 PFEIFFER, MOD. Hel. Viv. i. 421. 



Var. Stenotrema, CHEMNITZ, ed. 2, i. 376 (1846), pi. Ixv. figs. 



12-14, (1849). 

 Helicodonta hirsuta a FERUSSAC, 1. c. pi. L. A. fig. 3. 



I have thought it best to separate this from the succeed- 

 ing species, its characteristics being constant in Postplei- 

 ocene fossils as well as in recent individuals from Indiana, 

 Kentucky, Mississippi, Georgia, Alabama, and Louisiana. 



Ferussac considers this as var. a of hirsuta and gives 

 Stenotrema convexa Rafinesque as a synonym. His figure 

 is unmistakable. It appears, therefore, that Stenotrema 

 convexa Rafinesque is not hirsuta but the heavy form. 

 Its description in addition to that of the genus given in 

 vol. i. is as follows : " Nearly round, both sides convex, 

 smooth, 5 spires." I cannot, therefore, see any reason for 

 considering Rafinesque's species to be monodon, as so 

 many writers have done. In the continuation of the 

 Histoire, Deshayes considers Stenotrema as a variety only. 

 He has caused confusion by quoting Stenotrema convexa 

 Rafinesque as a synonym of hirsuta, and yet saying that 

 the same author has given the name of convexa to the 

 shell figured on pi. L. A. fig. 2, which is monodon. 



Pfeiffer also, in vol. i., gives Stenotrema convexa Raf. as 

 a synonym of monodon, on the authority of Ferussac, 

 though a reference to his figure would at once show that 

 he applied the name to the heavy form of hirsuta. 



