THE NAUTILUS. 1 17 



smooth, with faint growth-lines ; spire somewhat elevated, apex ob- 

 tuse ; whorls 3^—4, regularly rounded and somewhat inflated ; l.odv- 

 whorl large; suture well impressed. Aperture subcircular, slightly 

 angled above ; peristome nearly continuous, being appressed to the 

 body-whorl for only a short distance. 



Fig. 11. Alt. 2.25, diam. 2 mm. 



Fig. 16. Alt. 2.25, diam. 1.75 mm. 



Types (No. 3354 Coll. Walker) from Rock ford, Ills. Also from 

 Meyer's Lake, Canton and the Ohio Canal, New Philadelphia, 0. 

 Cotypes in the collection of the Academy of Natural Sciences. 



This, little species in years past must have been largely distributed 

 both as Lyogyrus gratia and Atnnicola parva, as I have received it 

 under these names from several different sources. From the former 

 it differs generically, and from the latter in its much smaller size and 

 regularly rounded whorls. It is in general appearance very much 

 like a minute A. limosa, but can at once be separated by its diminu- 

 tive size. As in many species of Amnicola, there are two forms, one 

 more slender than the other. From A. walkeri (pi. 5, fig. 12, cotype, 

 High Island Harbor, Mich.), which is about the same size, it differs 

 in being more globose, with less convex whorls, the suture being not 

 so deeply impressed, larger aperture and the appression of the inner 

 lip to the body-whorl. Named in honor of Dr. H. A. Pilsbry. 



Amnicola augustina Pils. PI. 5, figs. 13 and 14. 



Mr. Hinkley collected this species at Tuscumbia, Ala. Dr. Pils- 

 bry, who kindly compared specimens with the types, writes : " It 

 seems to me too close to augustina to be specifically separable, though 

 there are differences. Your shells have the whorls a trifle less con- 

 vex, the sutures therefore somewhat less deeply constricting, and the 

 narrow phase (males?) is narrower than the corresponding form in 

 augustina, but I would prefer to attribute what differences there are 

 to local causes." 



As A. augustina has not been figured, and the discovery of Mr. 

 Hinkley not only widely extends its range, but adds a new species to 

 the fauna of Alabama, it seems of sufficient interest to figure the 

 Alabama form and to record its occurrence at Tuscumbia. 



Fig. 13. Alt. 8, diam. 2 mm. 



Fig. 14. Alt. 3.25, diam. 2.25 mm. 



