NEW UROCOPTID LAND SHELLS FROM MEXICO 



By Paul Bartscii 



Curator, Division of Mollusks, United States National Museum 



During his recent botanical explorations in Mexico, Mr, C. R. 

 Orcutt was good enough to collect a large series of mollusks, which 

 has resulted in quite a number of sendings from various stations 

 visited by him. Among the material which has thus accumulated in 

 the National Museum are a lot of Urocoptid mollusks in need of 

 names which are here supplied. It should be remembered that No. 

 2594 of the Proceedings of the United States National Museum (vol- 

 ume 67, article 22, pages 1 to 5, with one plate), published in 1925, was 

 based on one of the early sendings of this expedition. In this, Holo- 

 spira {Holospira) orcutti^ Holosfira (Holospira) monclovana^ and 

 Holospira {Endisteinina) picta were described as new. 



HOLOSPIRA (COELOSTEMMA) EALSASENSIS, new species 



Plate 1, fig. IG 



Animal pale brownish ashy. Shell cylinclro-conic, thin, horn 

 colored, semitranslucent. Nuclear whorls 3, strongly rounded, form- 

 ing an almost cylindric apex, flattened at the top. The nuclear 

 whorls are marked on the early turns by a finely granular sculpture 

 only, while toward the end, the rib sculpture of the postnuclear 

 turns, slowly and feebly encroaches upon them. Postnuclear whorls 

 well rounded, marked by numerous rather strong, somewhat distantly 

 spaced axial ribs which are particularly conspicuous on the slowly 

 increasing cone of the shell, while on the middle turns they become 

 somewhat enfeebled, again increasing in strength on the last two 

 whorls. Suture conspicuously constricted. Periphery of the last 

 whorl well rounded. Base short with a very narrow slitlike umbili- 

 cus. The last portion of the last whorl is solute, and on this the axial 

 ribs become much reduced and irregular, closely spaced, and extend 

 all around the whorl. Aperture moderately large, subcircular, the 

 parietal wall portion flattened; peristome slightly expanded and 

 slightly reflected. When the shell is ground down, the pillar is seen 



No. 2653.— Proceedings U. S. National Museum, Vol. 70, Art. 4 



3044—26 



