184 THE NAUTILUS. 



(3.) Patula strigosa lil^l. var. lactea. 



This is a beautiful clear milk-white shell, with 5 2 whorls, sub- 

 carinated at the periphery. In the elevated forms the aperture is 

 nearly circular, as broad as high ; but in the depressed forms the 

 aperture is broader than high, obliquely subangulate. The lip is 

 simple, thickened, its terminations joined by a heavy callus, — the 

 thickening of the lip and callus is a shade darker than the body of 

 the shell. 



Height of the largest specimen 1 inch, breadtli li inch. 



Habitat, Rathdrum, Idal.o. 



The above varieties represent a colony of the largest specimens of 

 the Strigosa group that I ha*'e collected. They are an important 

 and very interesting addition to the series, and serve to confirm my 

 previous views on the relationship of what I call the Strigosa group. 

 This colony inhabits open places in the dense pine forests of the 

 mountains, overgrown with deciduous bushes. They hibernate among 

 leaves, brush and roots of trees and in protected and secure places, 

 generally on the north slopes of the mountains. 

 (4.) Patula strigosa UM. vav. jugalis. 



Shell umbilicated, depressed with numerous prominent oblique 

 striae ; spire very moderately elevated or depressed ; whoi'ls 51 some- 

 what flattened above, but more convex beneath, the las^t falling in 

 front, with two dark revolving bauds, one at the periphery and the 

 other above ; the body whorl subcarinated at its beginning but 

 more rounded as it appi*oaches the aperture ; suture well impressed ; 

 color ashy white with occasion?.! horn colored stains ; umbilicus 

 large, pervious, showing the volutions ; aperture oblique, ovate, 

 but in very depressed specimens the aperture is at right angles with 

 the axis of the shell; lip simple, thickened, its terminations approach- 

 ing and joined by a thick heavy callus, making the lip in very adult 

 specimens continuous. 



Height of the largest specimens j inch, breadth 1 inch. 



Height of the smallest specimens tV inch, breadth H inch. 



Habitat, Banks of Salmon River, Idaho. 



This is another interesting form of the very variable strigosa. It 

 inhabits stone piles, and other places where it can find shelter and 

 protection against the fatal rays of the summer's sun, close along the 

 banks of the river. It is interesting on account of its very depressed 

 form and the ovate form of the aperture, the heavy callus, join- 

 ing or "yoking" together the extremities of the lip. 



i 



