210 Descriptions of New Species of Pupada. 



Distribution. — Throughout Maine ; also in New Hampshire ; 

 Massachusetts ; New York ; and Norfolk, Va. 



Remarks. — Its nearest allied species is Isthmia Gouldii ; it 

 appears to be intermediate in size between the latter species 

 and 1. milium. The shell is one fifth smaller than I. Gouldii, 

 is lighter colored, more delicate in texture, and not so distinctly 

 striated. The outer lip is not depressed and the aperture is as 

 1 x-g as broad ; the teeth within the aperture of the shell are 

 less prominent, those at the base of aperture being scarcely ele- 

 vated. The color of the soft parts, the characters of the lingual 

 dentition and buccal plate are alse quite different. 



I take pleasure in dedicating this species to the Kev. E. C. 

 Bolles. 



Isthmia corpulenta, nov. sp. 



Fig. 7. 



Isthmia corpulenta Morse. 



Shell rimate perforate, elongate ovate, finely striated, 

 polished, translucent, dark olive brown ; apex round, obtuse ; 

 whorls four, convex, tumid, wider at the base ; aperture large, 

 sub-circular, with four obtuse teeth, one on the parietal margin, 

 one on the columellar margin, and two on the labrum ; peri- 

 stome slightly thickened and reflected. 



Length .10 inch ; breadth .06 inch. 



