N'orth American Helicidce. 29 



B. Pennsylvanica^ and the others above mentioned with H. 

 Mitchelliana, Saysjlgure is rather of the former, — his descrip- 

 tion and the figures of Dr. Binney of the latter forms. 



In the Boston Journal, Dr. Binney describes the umbilicus 

 as " nearly covered by the reflected lip," — probably he had not 

 then seen the imperforate JI. Mitc/ielliana, as no reference is 

 made to it. 



He remarks in the " Terrestrial Mollusks," that the surface 

 of II. clausa is " shining and its strise of increase delicate and 

 regular," — also that " the umbilicus in specimens entirely ma- 

 ture is covered, but, as commonly seen, a small opening still 

 remains." It would seem that Dr. B. did not know the Alaba- 

 ma variety, and alluded, when writing of the covered umbilicus, 

 to H. Mitchelliana Lea, which he puts in the synonymy of 

 H. clausa. 



Mr. W. G. Binney, in his "" Kotes on American Land Shells " 

 (Phil. Proc. 1857), states that the outline figures in Terr, Moll. 

 (PI. 4) do not represent II. clausa / they are, however, very 

 like my small Alabama or Tennessee specimens. 



De Kay describes IL clausa as having the umbilicus occa- 

 sionally entirely covered ; and states, erroneously, that it may 

 be considered as a Southern species, extending to New Jersey 

 and New York. 



Eeeve's figure of H. clausa (%. Q^Q), I have already referred 

 to as being H, Pennsylvanica. He gives another (fig. 694), 

 which may be the var. suhalholabris, but is more like H. huccvr 

 lenta Grould, without the parietal tooth. 



Helix: jflitchelliana I^ea* 



Synontm?* 



Helix Mitchelliana Lea Am. Phil. Trans. VI. 87, pi. 23, f. 71, 1836v 

 ««— clausa. De Kay N. Y. Moll. p. 31, ex parte, pi. 2, f. 13 ? 1843. 



