THE NAUTILUS. 29 



I found it this year from Horatio to Rich Mountain most plentiful in 

 the rocks scattered over the creek bottoms near the city of Mena, in 

 company with Gastro. demissa Brittsii and Poly, hirsuta uncifera. 

 The measurements were from 23 diam. 11 alt., to 28 mm. diam., 13 

 alt.; all 5^ whorls. In the Chastat Mountains four miles south I 

 found a smaller variety and got a few alive by digging down a couple 

 of feet. These ran from 16 diam., 8 alt., to 20 diam., 9 alt., with 

 not quite 5 whorls. 



124. Poly, thyroides (Say). DeKalb to Mena, occasionally, under 

 logs in damp situations. Pilsbry will have much to say on this 

 species, I think, as they run from the clausa size to the largest thy- 

 roides, and were so without regard to locality. The large size were 

 usually found in situations suitable for mnltilineata, while the smaller 

 were about the rocks and under logs upon higher ground. 



134-1. Polygyra Pilsbryi, n. sp. Shell imperforate, lens shaped, 

 about equally convex above and below, corneous-brown, the surface 

 rather glossy, sculptured above with strong, slightly curved, uneven 

 riblets, running with the growth lines; the riblets on the base very 

 uneven or interrupted as though composed of compressed radial lam- 

 ina?, arranged in several concentric circles. Whorls fully 5, slowly 

 increasing, the last carinated at the periphery, abruptly and shortly 

 derlexed in front. Aperture basal, hook-shaped or like the letter 

 " J " reversed; contracted by a long, arcuate parietal lamella, which 

 extends to the axis and is decidedly curved in, or entering, at its 

 outer end, and is connected with the end of the outer lip by a slight 

 callous ridge. Basal lip reflexed and prostrate, with a rather shal- 

 low median notch, much more conspicuous in a front than in a basal 

 view. Alt. 5, diam. 10 mm. Rich Mountain Station (Mt. Mena), 

 Polk Co., Arkansas, on mountain, by roadside leading from R. R. 

 station to the hotel, two specimens (one dead). 



Allied to P. labrosa, from which it differs in the remarkable scup- 

 ture and the form of the basal lip and notch. This shell was picked 

 up by my partner, Mr. Jolly. 



At the suggestion of Bryant Walker it is named in honor of Dr. 

 Henry A. Pilsbry, the very one who of late years has given con- 

 chologists the most delight, by his enormous zeal and industry, and 

 his untiring exactness. I was instructed by Mr. Walker to find 

 something for the occasion as large as indianorum or Ferrissi, but 

 this shell has unusual features to make up for the disappointment in 



