Descriptions of New Species of Pupadm. 209 



Isthmia ISoliesiaita, nov. sp. 



Fig. 4. 



Isthmia Bollesiaca Morse. 



Animal. — Dorsal portion of body light gray, disk nearly white. 

 Buccal plate of the same width throughout, slightly rouuded at the 

 ends; cutting edge without projections, finely striated. 



Fig. 5. Fig. 6. 



Buccal plate of I. Bollesiana. Lingual membrane of I. Bollesiana. 



Lingual formula 88,-12-1-12 ; central and lateral plates notched at 

 outer posterior corners; central plate square, widening posteriorly, 

 armed with three minute denticles, central one largest ; laterals having 

 two minute denticles apart, outer denticle nearly obsolete. Uncine 

 scarcely notched. 



Shell.— Minutely perforate, cylindrical ovate, delicately stri- 

 ated, sub-translucent ; apex obtuse ; suture well defined ; 

 whorls four, sub-convex ; aperture sub-orbicular, somewhat 

 flattened on its outer edge; with five teeth, one prominent and 

 rather curved on the parietal margin, two similar in form, the 

 lower one the smaller, on the columellar margin, and two 

 slightly elevated lamelliform teeth within and at the base ; 

 peristome sub-reflected and thickened. 



Length .065 inch ; breadth .035 inch. 



Station. — Under dead leaves and on bark in hard wood groves. 



