146 



PROCEEDINGS OF THE NATIONAL MUSEUM. 



VOL. XXXI. 



panded, flattened, but not revolute peristome. Internal column thin, 

 hollow throughout, smooth, marked only by lines of growth, some- 

 what ol)lique and contracted in the last whorl, wider in the penukimate 

 and increasing gently in diameter posteriorly to the beginning of the 

 terminal cone. The column in its widest place is equal to about one- 

 fourth of the diameter of the shell. The unique type has 15 whorls 

 and measures: Length, 16 mm.; diameter of eleventh whorl, 4.5 nun.; 

 diameter of penultimate whorl, 4.2 mm. 



The type. Cat. No. 109215, U.S.N.M., was collected by C. H. T. 

 Townsend, at Cerro Chilicote, Chihuahua, Mexico. 



HOLOSPIRA (HAPLOCION) FUSCA von Martens. 



There are three specimens of this species in the collection of the 

 U. S. National Museum, Cat No. 1()2323, U.S.N.M., collected by (lod- 

 man, at Omilteme, Guerrero, Mexico. The two perfect specimens 

 measure: 



Mensaremenls of Ilolospirn Haplocion fusca. 



HOLOSPIRA (HAPLOCION) LICHENOPHORA, new species. 



Plate IV, fig. 7. 



Shell cylindric-conic, dark horn brown, beautifully variegated with 

 irregular white blotches, which appear as white incrustations upon the 

 brown background when examined under the microscope. Nuclear 

 whorls mcderatel}^ rounded, verj^ minutely granulose, scarcely ditt'er- 

 entiated from the succeeding turns. Terminal cone gently tapering, 

 having the whorls moderately rounded and marked with ill defined 

 and irregularly spaced riblets. The whorls of the cylindrical portion 

 are moderately rounded, and have the greatest convexity a little pos- 

 terior to the middle, which lends them a somewhat shouldered appear- 

 ance. The riblets on the cylindrical part of the spire are represented by 

 mere lines of growth. Sutures decidedly impressed. Last whorl with 

 the lines of growth strengthened, scarcely ribbed, periphery slightly 

 angulated. Base short, well rounded, marked by the strong lines 

 of growth which extend into the moderately broad, open, umbilicus. 

 Last whorl decidedly f i-ee at its extremity. The free portion is a little 

 more than 2 mm. wide at the decidedly angulated junction of the 

 parietal and outer wall. The junction of the columellar and parietal 

 wall is also somewhat angulated and the parietal wall itself is not flat. 



