lymnvehxe of north America. 355 



Remarks : Galba attenuata resembles certain forms of reflexa, 

 particularly reflexa zvalkeri. Its flat-sided, turreted whorls, elongated 

 spire, heavy columellar plait and particularly the absence of the convex 

 swollen penultimate whorl will distinguish it from reflexa. The body 

 whorl is also more convex than in either reflexa or exilis. Galba exilis 

 has more flat-sided whorls and a longer and narrower aperture. The 

 aperture varies somewhat in some individuals being rather narrow 

 while in others it is wider or even expanded and flaring. The flat- 

 ness of the whorls varies also, in some individuals they are almost 

 as flat as in exilis while in others they are almost as rounded as in 

 typical reflexa. The whorls of attenuata are, however, always pe- 

 culiarly flattened in the middle and rounded toward the sutures above, 

 besides being more regular in their increase than in reflexa or exilis. 

 Strebel figures several specimens which resemble some examples of 

 Galba elodes jolietensis. 



Say's types of attenuata are preserved in the Academy of Natural 

 Sciences of Philadelphia. One specimen has seven whorls, which are 

 flat-sided. Subulata Dunker is undoubtedly a synonym the spire whorls 

 being wide and more flat-sided than typical attenuata. Mexicanus 

 Ziegler is also a synonym. Haldeman's figures are excellent and cor- 

 rectly represent the species. 



Galba danielsi (Baker). Plate XXXVIII, figures 1-8. 



Limnophysa reflexa Blatch. and Ashley, Ind. Geol. & Nat. Res., XXV, 

 p. 248, 1901. 



Lymncea danielsi Baker, Nautilus, XX, p. 55, September, 1906. 



Shell : Elongated, attenuated, of medium thickness ; periostracum 

 ranging from very light-yellowish horn to dark chestnut or purple; 

 surface shining, growth lines generally fine and close-set, but oc- 

 casionally, as near the aperture, coarse and often raised into ridges ; 

 last whorl often malleated ; spiral sculpture of fine impressed lines ; 

 nuclear whorls resembling those of reflexa in outline, spermaceti-white 

 in color; whorls 7, flat-sided or slightly convex, slowly increasing in 

 diameter ; the body whorl is very large and much inflated ; spire long 

 and sharply attenuated, longer than the aperture ; sutures impressed ; 

 aperture ovate or semi-lunate, often a little triangular, rounded below, 

 acutely angled above, somewhat flaring; peristome sharp, simple, 

 bordered by a dark purple or chocolate band in many specimens ; 

 parietal wall with a thin callus ; inner lip narrow but wider than in 

 reflexa, reflexed, generally closely appressed to the shell and almost 

 closing the umbilical region, leaving a small chink; axis strongly 

 twisted, almost gyrate, forming a heavy ascending plait ; interior of 

 aperture varying from white to dark purple. 



