THE NAUTILUS. 



is the distinguishing point of the genera, like tlie fissure of Schizos- 

 toma. I am of the opinion that Mr. Lea's specimens are young 

 Angitrema armigera Say, for the following reasons : The young of 

 armigera is generally smooth, is fusiform, thin, obtusely conical and 

 of various shades and markings, from a light straw-color to purple, 

 occasionally seven handed while six is common ; the aperture is 

 large and rhomboidal, obtuse longitudinal thickenings are common 

 on body whorl, a light line under the suture is also common in banded 

 and purple specimens, base channel well defined. Polar point of the 

 operculum well removed from the margin. There is no other species 

 found in the Wabash that has so many points of resemblance ; about 

 the only point of difference is the number of whorls, five to six in the 

 young armigera I have, while Mr. Lea's description says seven. 



There are some other species I think must be referred to Angitrema 

 armigera, but additional specimens from other localities are needed 

 to fully determine the identity. — A. A. Hinkley. 



THE SUBSPECIES OF PYRAMIDULA ALTERNATA. 



BY HENRY A. PILSBRY. 



Pyramidula alternata knoxensis, n. v. 



A more robust, larger shell than typical P. alternata, with more 

 widely open umbilicus; dull rusty brown, with comparatively incon- 

 spicuous or much- reduced flame-markings. Whorls 5^, not carinated. 

 Sculpture of fine and even rib-striae, but little weaker on the base, the 

 whole covered with a secondary sculpture of fine wrinkles, partially 

 cuticular, and running a little more obliquely than the rib-striae. 

 This minute wrinkling is barely visible to the naked eye, but is much 

 stronger than in other forms of P. alternata, and gives the surface a 

 peculiarly didl appearance. 



Alt. 11, diam. 23, width of umbilicus ('4 mm. (Knox Co., Tenn.). 



Alt. 11, diam. 23, width of umbilicus 7 mm. (Laurel Creek Gap). 



Alt. 13, diam. 25, width of umbilicus 7^ mm. (Hazel Creek). 



This remarkable race of P. alternata belongs, so far as we know, 

 to the valleys of the western slope of the Great Smoky mountains, 

 extending into the valley of East Tennessee. It was first found by 

 Mrs. George Andrews, in Knox county, Tenn. During the past 

 summer Mr. das. H. Ferriss found it in Cade's Cove, at Laurel Creek 



