70 BULIMULUS-SOUTH AMERICAN. 



short-conic, its outlines a trifle concave above ; apex obtuse, the 

 nepionic whorls showing shallow, short ripples in the young, mainly 

 lost by wear in the adult. Whorls 5I-6J, moderately convex, the 

 last two more convex, last whorl either quite obese or somewhat com- 

 pressed ; sutures well impressed. 



Aperture subvertical, white within, ovate, acutely angular above, 

 about one-half as long as shell ; outer lip regularly arcuate, acute 

 and unexpanded ; columella nearly straight, the margin reflexed 

 above. 



Alt. 22, diarn. 14 mill.; alt. of aperture 12 mill. 



Alt. 24, diam. 13 mill.; alt. of aperture 12 mill. 



Montevideo, Uruguay, in the plain back of the " Cerro," on this- 

 tles (Dr. Wm. H. Rush, U. S. N.). 



This species resembles B. apodemetes d'Orb. in contour, but the 

 apex is decidedly larger, the outlines of the spire contracted above, 

 columella straighter, and finally the nepionic whorls, which appear 

 quite smooth even in young apodemetes, are seen to be distinctly 

 though shallowly sculptured when the apex is unworn. It is more 

 closely allied to B. sporadicus and montevidensis, but in the latter 

 species the spire is much longer and more attenuated, the sutures 

 shallower, and the surface without streaked coloration. I have not 

 seen Strobel's var. bonariensis, but from his calling it thinner than 

 sporadicus I conclude that it must differ from the present form, 

 which is fully as solid as the thickest sporadicus or montevidensis 

 which I have seen. 



B. RUSHII Pilsbry. PI. 12, fig. 47. 



Shell umbilieate, globose-ovate., rather thin but solid, light-yellow- 

 ish. Surface with inconspicuous growth wrinkles and extremely fine, 

 close incised spiral stria, visible only above the periphery. Spire 

 very short, conic, the apex obtuse. Whorls slightly over 6, moder- 

 ately convex, the suture shallow but well marked. Aperture slightly 

 oblique, ovate, a trifle over half the total length of shell ; peristome 

 simple, unexpanded. The columellar margin broadly dilated above. 

 Alt. 19, diam. 14 mill.; alt. of aperture 10 mill. 



Maldonado, Uruguay (Dr. W. H. Rush). 



Bulimulus Rushii PILS., Nautilus, x, Nov. 1, 1896, p. 78, (name 

 only) ; Proc. Acad. N. S. Phila., 1897, p. 18 (Feb. 23). 



