FOSSILS OF THE W AVEULY GUOUP. 2(jl 



periphery, altlioug'h Hatteued on the top of the vohitioii. The iii(hvi(hial 

 figured is somewhat smaller than the sj)ecimen used and figured by Dr. C. 

 A. White in Lieutenant Wheeler's Eejiort above cited, but possesses all the 

 characters of those specimens. 



Formation and locality. — In limestones near the base of the Wahsatch 

 limestone, of the age of the Waverly group of Ohio, at Dry Canon, Oquirrh 

 Mountains, and Logan Caiion, Wahsatch Eange, Utah. Collected by S. 

 F. Emmons and J. E. Clayton. 



EUOMPHALUS (StRAI'AROLLUS) OpHIRENSIS 1). sp. 

 Plate IV, li};s. ai--J7. 



Shell of medium size, broadly conical or suljtrochiforni; height equal 

 to two-thirds the greatest transverse diameter of the base; composed of 

 four and a half to five volutions, which are closely coiled, so as to rest nearly 

 upon the surface of the succeeding, ones; four of the volutions obliquely 

 compressed on the outer upper portion, and sharply rounded on the periphery 

 and below, giving a somewhat convex trochiform aspect to the coils. 

 Umbilicus broad and deep, exposing moi-e than one-half of each of the 

 preceding whorls, which are strongly rounded and full. Transverse section 

 of the volution obliquely and irregularly ovate, narrow, and somewhat 

 pointed at the upper end at the junction of the volutions, rounded on the 

 inner, and obliquely flattened or depressed-convex on the outer surfiice. 



Surface of the shell marked only by very fine transverse lines of 

 growth, which have a slightly backward curvature as they cross the volu- 

 tion. 



This species has something of the form and general appearance of 5^. 

 umbilicus M. & W., from the Coal-Measures (see Geol. Rept. Ills., vol. ii, pi. 

 27, fig. 1), but is more depressed and proportionally broader, without the 

 horizontal flattening on the ujjper surface of the volutions, which are instead 

 obliquely compressed nearly in the dircition of the slojx- of the s])ire. 



Formation and localitji. — In limestones of the ngc of the Waverly group, 

 at Dry Canon, Oquirrh iMoniitains, Utidi. Colleet.MJ by d. E. Clayton. 



