1919.] 



NATURAL SCIENCES OF PHILADELPHIA. 



217 



Fig. 5. — Averellia hinkleyi. 



This little shell has been in the collection for many years under 

 the name "H. opal McNeil Ms." It is more narrowly umbilicate 

 than Z. mmja, with the last whorl wider, viewed from above. 

 Averellia (Trichodiscina) hinkleyi n. sp. Fig. 5. 



The shell is broadly and openly umbilicate, discoidal, the spire 

 sunken a little; between cinnamon and cinnamon-brown, not banded. 



Surface dull, very 

 densely and minutely 

 papillose, and sparsely 

 covered with long hairs 

 arranged in oblique 

 lines. These hairs are 

 about 0.75 mm. long 

 and about 1 mm. apart. 

 On the penult whorl they persist in the sutural region only, and the 

 first 1^ whorls are smooth, without papillae or hairs. The whorls 

 are convex, the last rounded peripherally, the periphery above the 

 middle; very deeply descending in front. The aperture is sub- 

 horizontal. Peristome pale vinaceous, narrowly reflected, the in- 

 sertions of the lip remote, parietal callus very thin. 



Alt. 5, diam. 12.3 mm.; width of umbiHcus 3.7 mm.; of aperture 

 5 mm. ; 4| whorls. 



Mountains west of Livingston, Guatemala, A. A. Hinkley, 1913. 

 Type and paratype, No. 107,533 A. N. S. P. 



Distinct by its concave spire, very deeply descending last whorl 

 and long hairs. The form and peristome are much as in il. macneili 

 (Crosse), but there is no trace of the peculiar pits of that species. 

 Thysanophora rhoadsi n. sp. Fig. 6. 



The shell is perforate, conic, light brown, dull. The spire is high, 

 a little convexly conic. Whorls very convex, the suture deeply 



impressed. Sculpture of light, fine, somewhat ob- 

 lique growth wrinkles, with much more strongly 

 retractive cuticular raised threads superposed 

 over them, but mainly worn from the type speci 

 men. The last whorl has rather strong, irregular 

 grow'th-wrinkles, and only slight traces of the 

 retractive threads. The aperture is oblique, 

 broad, columellar margin reflected. 

 Alt. 2.8, diam. 2.5 mm.; 5 whorls. 

 Gualan, Guatemala, collected by S. N. Rhoads. 



Fig. 6. 

 Thysanophora rhoadsi. 



Type, No. 114,836 A. N. S. P. 



