THE NAUTILUS. 29 



VI. Ancylus kirklandi n. s. PI. II, figs. 1-12. 



Shell Iarg6 for the genus, thin, transhicent, horn-colored; broadly 

 oval or obovate, sides nearly equally curved, ends broadly rounded ; 

 quite elevated ; apex subacute, behind and to the right of the middle, 

 and decidedly turned to the right ; posterior and right slopes straight 

 or slightly concave, anterior slope quite convex, left slope decidedly 

 convex ; surface with the growth lines regular and distinct and more 

 or less rippled by transverse wrinkles, which frequently tend to form 

 feeble, irregular radial riblets. 



Fig. 1 (type) : Length 8, breadth 5^, alt. 2.5 mm. 



Grand Rapids, Mich. : Length 9.25, breadth 5.5, alt. 2.5 mm. 



Grand Rapids, Mich. : Length 8.25, breadth 5, alt. 2 mm. 



Hardy, Arkansas: Length 6.50, breadth 5, alt. 2 mm. 



Fig. 4 : Length 6, breadth 4.50, alt. 2 mm. 



Fig. 7 : Length 5.75, breadth 4, alt. 2 mm. 



Fig. 10 : Length 5.25, breadth 3.25, height 2 mm. 



This fine large species is a well-defined one and has wide range, 

 extending from Trenton, N. J., w^est to Hardy, Ark. The specimens 

 from the last locality were cited as A. holdemani by Pilsbry (Proc. 

 P. A. N. S., 1900, p. 457), and, from this identification, that species 

 was placed among those with smooth apices in the Naut. xvi, p. 88. 

 A recent examination by Dr. Pilsbry of the type of ^. holdemani has 

 shown that that species has a striate apex and, therefore, does not 

 belong in Laevapex at all. A. kirldandi is distinguished by its large 

 size, decidedly elevated shape and its prominent, subacute apex, 

 which is decidedly turned to the right. There is some considerable 

 variation in shape, as shown by the above measurements, some 

 examples being more elongated with nearly parallel sides. There is 

 also considerable difference in height. But in all cases the subacute, 

 prominent apex and the convex, left slope are characteristic, and 

 always distinguish it from fuscus, in which the apex, even in the 

 more elevated examples, is always bluntly rounded and the left slope 

 scarcely convex. 



Kirklandi is more nearly related to the Florida shell herein re- 

 ferred to as obscunis than to any other species, but differs by its 

 broader form, greater elevation, more acute and more eccentric apex 

 and greater convexity of the left lateral slope. 



The finest specimens of kirklandi come from Grand River, Kent 

 county, Mich., where they have been collected in great abundance 



