1906.] NATURAL SCIENCES OF PHILADELPHIA. 547 



Polygyra kiowaensis (Simpson). PL XXI, figs. 13, 17-20. 



Helix (Mesodon) kiowaensis Simpson, Proc. U. S. Nat. Mus., 1888, p. 450. 



Pilsbry, Man. Conch., VIII, p. 155, pi. 50, figs. 13-15, with var. arkansaensis, 



p. 156, pi. 50, figs. 11, 12. 

 Helix {Mesodon) kiowaensis Simps., Pilsbry, Proc. A. N. S. Phila., 1889, p. 414, 



pi. 12, figs. 11, 12 (jaw and teeth). 

 Polygyra (Mesodon) kiowaensis Simpson var. arkansaensis Pils., Nautilus, 



IV, p. 131 (March, 1891). 

 Mesodon kiowaensis Simpson var. arkansaensis Pils., Sampson, Moll, of 



Arkansas, p. 192. 



This is a solid, compact little "Mesodon," readily distinguished from 

 P. binneyana and from the small umbilicate form of P. indianorum by- 

 its wide spire and narrower last whorl, and by the very narrow expan- 

 sion of the internally thickened lip, which is without traces of teeth. 



It was originally found at Kiowa and Limestone Gap, I. T., two 

 stations (not towns) on the M. K. & T. R. R., where Mr. C. T. Simpson 

 collected in 1888. A single bleached shell was taken at Eufaula, I. T. 



In 1903 we worked a few days, April 9-11, at and near the Gap, and 

 on the adjacent Sandstone "Mountains" immediately eastward. 

 Helices were found chiefly under stones, together with copperheads 

 and rattlesnakes. We found P. kiowaensis very rare. Pilsbry got two 

 living ones, one of them not full grown, and four dead shells, three of 

 them more or less broken; Ferriss a few more. In all of them the 

 umbilicus is slightly narrower than in a cotype from Kiowa received 

 from Mr. Simpson (PI. XXI, fig. 20). 



On the dry southern slope of Magazine Mountain, Logan Co., Ark., 

 we found several dead and bleached shells similar to those from Lime- 

 stone Gap, only two entire and one broken, although a great deal of 

 time and labor was spent in the search. They occurred around and 

 under rocks (PI. XXI, fig. 13). 



The only other locality known is from near Hot Springs, Garland Co., 

 Ark., where Mr. Sampson in 1890 found the types of what was described 

 as var. arkansaensis (Pi. XXI, figs. 17, 18). These specimens are some- 

 what more robust than the types of kiowaensis, with the aperture 

 slightly larger and the umbilicus smaller. The specimens cohected by 

 us at Magazine Mountain and Limestone Gap demonstrate however 

 that the differences in the umbilicus and the shape of the mouth are 

 inconstant ; and we are now convinced that the varietal distinction is 

 untenable. The name arkansaensis should therefore be dropped. 



The scarcity of specimens at the three widely separated localities 

 known, while many intermediate localities have been carefully searched 

 for snails, shows P. kiowaensis to be one of the rarest of American Helices. 



Measurements of the specimens in Coll. A. N. S. follow, the dimen- 

 sions of aperture including the peristome: 



