452 THE CHICAGO ACADEMY OF SCIENCES. 



terial has been included in preblei which Dr. Dall places in binneyi, 

 evidently from a misconception of the true binneyi. Binney (p. 31) 

 has confused this species with Galba emarginata mighclsi. An examin- 

 ation of the axis of both species shows them to be true Stagnicolas 

 and not rightly placed in Radix which has a distinctly gyrate axis. 

 Preblei will doubtless be found to be a common species in the waters 

 draining into Hudson Bay. 



Galba randolphi (Baker). Plate XVIII, figure 6; plate XLVI1I, 



figures 5-12; plate XLVI, figure 13. 



Limncea ampla Randolph, Nautilus, XII, p. 110, 1899. 



Limncea emarginata var. mighelsi Baker, Bull. Chi. Acad. Sci., II, No. 4, 

 pp. 196, 198, 1900 (not of Binney). 



Lymncea randolphi Baker, Nautilus, XVIII, p. 63, Oct., 1904. 



Lymncea (Radix) randolphi Dall, Alaska Moll., p. 71, pi. 1, figs. 3, 4, 1905. 



Limncea randolphi Whiteaves, Ottawa Naturalist, XIX, p. 65, 1905; Nauti- 

 lus, XIX, p. 3, 1905. 



Shell : Large, thin, more or less inflated ; whorls 5, inflated, dis- 

 tinctly angulated at the shoulder and constricted at the suture, fre- 

 quently decollated; spire short, occupying less than half the length of 

 the shell; in some specimens the first three and one-half whorls are 

 small and regularly wound, and the last whorl abruptly enlarges to 

 more than four times the diameter of the preceding whorls, sometimes 

 causing the upper spire whorls to appear as though set upon a ped- 

 estal; nuclear whorls \y± in number, the first part of the whorl is 

 rounded and very small, the second very large, rounded ; the nuclear 

 whorls are very rough, with a satin finish sculpture; in certain lights 

 there seem to be very fine spiral striations ; (pi. XLIX, fig. O) ; 

 sutures deeply impressed, the whorls constricted near this region ; sculp- 

 ture consisting of close-set, regular lines of growth crossed by fine, 

 impressed spiral lines ; the surface is strongly malleated in many 

 specimens and in some individuals raised spiral ridges are formed on 

 the body-whorl; aperture very large, ovate, narrowed at the posterior 

 end by the sutural constriction ; the anterior end of the aperture is 

 rounded and much produced; the aperture is made continuous by the 

 elevation of the inner lip which is more or less reflected, thin and 

 sharp; outer lip very thin, a trifle patulous in many specimens; in 

 some specimens the inner lip is appressed to the body whorl while in 

 others it scarcely touches it joining the outer lip at a sharp angle; 

 pillar with a twisted axis, sometimes slightly sinuous ; umbilical chink 

 deep, rather widely open in some specimens ; color pale horny, with 

 sometimes a dark line at resting stages, dead specimens become chalky 

 white. 



