NATURAL SCIENCES OF PHILADELPHIA. 59 



a somewhat crenated appearance; lower half of last turn marked with a few 

 distinct revolving raised lines. 



Length, 0-43 inch; breadth, 0-19 inch; length of aperture, Oil inch; 

 breadth of do., 0-10 inch. 



, This species may be at once distinguished from the last by its less convea 

 whorls, and the absence of revolving ridges or lines, excepting on the lower 

 part of the body volution, and the one just below and above the suture. As 

 in the last, its apical whorls are smooth. The only good specimen of it seen 

 is considerably smaller than the adult size of the last described species. 



Locality and position. Same as last. 



Carinifex Binneyi, Meek. 

 Shell attaining a large size, depressed subglobose in form ; spire scarcely 

 rising above the body whorl; umbilicus large, but rapidly contracting within. 

 Volutions about three and a half, increasing very rapidly in size ; those of the 

 spire a little convex, last one forming more than nine-tenths the entire bulk 

 of the shell, widest above, and produced below so as to form a prominent 

 ridge or subangular margin around the widely excavated umbilical region ; 

 all without revolving carina?. Aperture large, obovate, being widest above 

 and narrowed abrubtly to a subangular termination below. Lip remarkably 

 oblique, apparently reflexed and strongly produced forward above. Surface 

 marked with extremely oblique lines of growth, which sometimes form little 

 regular costne. 



Height, 0-59 inch; breadth, 1 inch; height of aperture, about 0-50 inch ; 

 breadth of do., 0*54 inch. 



This species differs too widely in nearly all of its characters to require any 

 comparison with C. Newberryi, the typical and only known living species, 

 which it also exceeds in size. 



All of the specimens of this species in the collection are incrusted by a 

 laminated, smooth calcareous deposit, that has to be removed before the sur- 

 face marking can be seen. This is continuous over the suture, and covers all 

 the volutions of the spire. At first I was inclined to think this might have 

 been secreted by the mantle of the animal enveloping the whole shell; but 

 farther examinations have led me to think it more probably merely an 

 inorganic incrustation, precipitated over the surface after the death of the 

 animal. Named in honor of W. G. Binney, Esq. 



Locality and position. Fossil Hill, Hotspring Mountains, Idaho Territory. 

 Apparently of Miocene or later age. 



Carinifex (Vortifex*) Tryoni, Meek. 

 Shell depressed subglobose, approaching subdiscoidal, the spire being much 

 depressed. Volutions four and a half to five, increasing rather rapidly in size ; 

 those of the spire slightly convex; last one sometimes becoming^ little con- 

 cave on the upper slope near the aperture, and more or less ventricose below, 

 the most prominent part being near the rather small, deep umbilicus, into 

 which it rounds abruptly; all rounded on the outer side, and without any 

 traces of carina? or revolving markings. Suture well defined. Aperture 

 rather large, subcircular, its height being to its breadth about as 29 to 34; lip 

 sharp, oblique, and produced forward above, faintly sinuous at the middle ot 

 the outer side as well as at the inner side of the base, where it is a little 

 thicker. Surface ornamented with small, distinct, regular ridges, and much 

 finer lines of rowth running parallel to the very oblique outline of the lip 



Height, 0-35 inch; breadth, 0-64 inch; height of aperture, 0-29 inch; 

 breadth of do., 0-34 inch. 



This shell differs from the last, not only in its smaller size, more rounded, 

 less rapidly enlarging whorls, and more prominent spire, but particularly in 

 its very much less excav ated umbilical region. It evidently vanes consuler- 



* I propose the subgeneric name Vorli/ex for these shells, which differ from the typical 

 forms of Carinifex. 



1870.] 



