308 THE CHICAGO ACADEMY OF SCIENCES. 



on the outer edge of Pujal Lake and under a thorny bush near Yalles, 

 Mexico (Hinkley). No other records of the ecological relations of 

 this species have been seen by the writer. 



Remarks: Cubensis is the most common Lymmeid in Mexico, 

 Cuba and certain of the West Indies. It varies somewhat in corpulency 

 and in the height and acuteness of the spire. It is easily known by its 

 generally rotund shell, rather short broad spire, large rounded aper- 

 ture, rounded, somewhat turban-shaped whorls and by its triangular, 

 roundly folded inner lip. This last character will easily separate it from 

 unibilicata and aspirans. Truncatula rather closely resembles cubensis, 

 but the spire in cubensis is shorter, the whorls are wider and more 

 rotund, the aperture is rounder and the inner lip is differently reflected. 



In specimens from Mexico the inner lip may be rolled over into 

 the umbilical chink or rolled upward, somewhat as in the race aspirans. 

 Cuban specimens average somewhat more obese than specimens from 

 Mexico and Florida. 



Both Clessin and Gibbons have called attention to the similarity 

 of certain forms of truncatula to cubensis. This similarity is due, un- 

 doubtedly, to parallel development. The life zones of the two species 

 are widely separated and there is little fear of confusion in the iden- 

 tity of cubensis. Galba humilis has been mixed with cubensis and 

 may be separated by its more elongated and sharper spire, less rounded 

 whorls and differently shaped inner lip. 



It is believed by the writer that the references to Lymnara uni- 

 bilicata by Adams, from Jamaica, are founded on specimens of cuben- 

 sis. See under Galba unibilicata for a discussion of this subject. The 

 single specimen of Lea's lecontii seems referable to cubensis, speci- 

 mens from Mexico being almost identical with it in form. 



Galba cubensis aspirans (Pilsbry). Plate XXVII, figures 17-19. 



Lymncea cubensis aspirans Pilsbry, Nautilus, XXIII, p. 120, February, 1910. 



Lymna?a cubensis Browx, Journ. Couch., X, p. 266, 1903. 



Shell : Elongate-ovate or fusiform, solid ; periostracum light 

 yellowish to reddish horn ; surface shining, growth lines heavy, con- 

 spicuous ; spiral lines absent, or if present, almost indistinguishable; 

 nuclear whorls similar to those of techella; whorls o]/ 2 to (i convex, the 

 body whorl ovately ventricose ; spire acutely conical, wide, about equal 

 to the aperture in length ; sutures well impressed ; aperture elongate- 

 ovate ; outer lip simple ; inner lip reflexed to form a flat shelf which is 

 narrow and is not compressed at the junction of the columella with 

 the parietal wall ; parietal callus thin, white ; umbilical chink very large, 

 deep, overhung by the inner lip which emargines it; axis as in cubensis. 



