﻿A NEW ASHMUNELLA FROM NEW MEXICO 

 B^ PAUL BARTSCH 



Some time ago the United States National Museum received two 

 specimens of Ashmunella which represent an undescribed species. 

 The shells were collected by Mr. C. H. T. Townsend on the slopes of 

 the ridge on the south fork of Ruidoso river, about five miles above 

 the town of Ruidoso. at an altitude of 8,500 feet. Ruidoso is in the 

 Sierra Blanca, Mescalero Apache Indian reservation, Lincoln county. 

 New Mexico. 



ASHMUNELLA TOWNSENDI new species 

 Shell moderately elevated, rather thin, axially strongly ribbed, and 

 closely spirally incised, pale brown to bluish-white. 



The shell examined under a compound microscope shows three 

 distinct developmental stages. The first or nepionic consists of one 

 and three-quarter well-rounded volutions, the earliest portion of 

 which shows faint traces of obscure axial lirations which are gradu- 

 ally replaced by rather distant, interrupted, feebly papillose axial 

 lira;, the lirae and papillae becoming- stronger and more crowded as 

 the shell advances in age. Near the terminus of the nepionic stage 

 several strong, very oblique, posteriorly slanting folds make their 

 appearance and the finer sculpture becomes again enfeebled. The 

 second or neanic stage consists of about one and one-fourth well- 

 rounded turns, and is marked by many closely placed axial lirations 

 which are somewhat stronger and a little more distantly placed in 

 the beginning than in the latter portion of this stage. There are 

 faint papilla present which are irregularly scattered and appear in- 

 differently on the lira or interliral spaces. The entire neanic portion 

 is also marked by very fine, closely-placed, wavy spiral lines. The 

 third or ephebic stage consists of two and one-third volutions, the 

 last one of which shows a tendency toward peripheral keeling. The 

 whorls are marked by many strong, sublamellar, axial ribs which have 

 their posterior slopes much shorter than the anterior. These ribs pass 

 undiminished from the summit of the whorls over the periphery into 

 the moderately wide umbilicus. The entire ephebic portion is marked 

 by many subequally spaced, strongly incised, spiral lines, which 



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