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Mexican Species. 

 Pseudohyalina Mazatlanica, Pfeiffer. 



Plate 4, figure 59. 



Depressed, Timbilicate, costato-striate, corneous ; whorls 4, 

 somewhat convex, the spire slightly raised ; last whorl narrow, 

 scarcely descending at the aperture; umbilicus equalling -J of 

 the diameter; aperture oblique, Innately rounded, its margins 

 approaching. 



Diam. 2"3, altitude 1 mill. 



Mazatlan, Mexico. 



