NO. nil. PROCEEDINGS OF THE NATIONAL MUSEUM. 343 



shell. A careful scrutiny of a series of P. cMricahuana shows that 

 occasional sparse, spiral, incised lines are found on some individuals, 

 so that the jiresent shell may only represent a dwarf race of it with 

 more emphatic sculpture. However this may be, the difference is so 

 great as to form at least a well-marked variety worthy of a name. 



The types (Xo. 107610, IT.S.K.]\r.) were collected at Bland, i^ew Mexico, 

 at an elevation of 8,000 feet above the sea. Mr. Ashmun notes that in 

 coming down the mountains toward Bland, the typical P. cMricahuana 

 was abruptly replaced by P. ashmuni. 



POLYGYRA PSEUDODONTA, Dall. 



Shell closely resembling P. ashmuni in form and size, but with the 

 whorls slightly flattened above and below and of a yellowish straw 

 color instead of livid brown, the spiral striation less sharp and largely 

 obsolete. The aperture with a narrow reflected lip, pink or whitish, 

 which has on the internal edge of the basal part a slight callosity which 

 is divided by a narrow sulcus in the direction of the coil of the shell. 

 Within the aperture and nearly midway between the outer and pillar 

 lil)S is a small low simple short oblique parietal tooth, or ridge, with 

 the outer end nearer the pillar. Greater diameter of the shell, 13.5 to 

 15 mm.; minor diameter, 11 to 13,5 mm.; altitude, 5.5 to 7 mm. in 

 different specimens. 



White Oaks, New Mexico, at an altitude of 7,500 feet, Ashmun. Tyjie, 

 No. 107611, U.S.jST.M. The aperture of this form is quite peculiar. 



With these shells were the following species, all said to be from New 

 Mexico, but of which the exact locality was not stated : Gonulusfulvus, 

 Vitrea arhorea, V. indentata, Yallonia eyclophorellaj Vitrina Umjnda, 

 Gould, Helicodiscus Imeafus, Pupa armifera, and Gionella luhrica. 



POLYGYRA MEARNSII, Dall. 



(Plate XXXII, figs. 7, 8, 11.) 



Fohjgiira mearnsU, Dali>, Pioc. U. S. Nat. Mus., XVIII, p. 2, 1895. 



Shell depressed, 5-whorled, of a pinkish-brown color, sculptured only 

 with moderately conspicuous incremental lines; spire much depressed, 

 but not quite flat, a iniclear whorl and a half smooth, the rest striated 

 more or less distinctly; in perfectly fresh specimens the surface is 

 probably polished ; suture very distinct; periphery rounded, but nearer 

 the upper surface of the whorl; base rounded, but having a compressed 

 appearance; umbilicus deep and narrow, except that a small portion of 

 the half whorl preceding the last whorl is visible; termination of the 

 last whorl slightly descending above and, below the periphery, strongly 

 constricted behind the reflected lij) of a very oblique aperture; \)en- 

 stome somewhat flexuous, reflected, nnited over the body by a distinct 

 callus; body with two converging lamella', not united at the inner 

 ends into a A, the basal lamella stouter and its outer extreme bent 



