316 EEPOET UNITED STATES GEOLOGICAL SURVEY. 



higher, and, so far as I am aware, none of tliem, except perhaps the 

 UuUmella, have yet been discovered elsewhere. The stratigraphical po- 

 sition appears to be either at the top of the Colorado Group or near the 

 base of the Fox Hills Group,' or the equivalent of Nos. 4 and 5 of the 

 Upper Missouri Cretaceous section. 



TUBEITELLA (ACLIS?) MICKOKEMA Meek. 



Plate 9, fig. 8 a. 

 Turritella {AcUs?) microjiema Meek, 1873, An. Eep. U. S. GeoL Surv. Terr, for 1872, p. 504. 



"Shell small, terete or elongate-conical; volutions about nine, nearly 

 flat, sometimes moderately convex, increasing gradually in size, last one 

 rounded or obscurely subangular in the middle ; suture linear to mode- 

 rately distinct ; aperture rhombic-ovate, angular above. Surface orna- 

 mented by fine, regular, rather crowded, revolving lines, six or eight of 

 which may be counted on each volution of the spire. 



"Lenglih of the largest specimen seen, 0.50 inch; breadth, 0.18 inch; 

 angle of spire, about 19°, with shghtly convex slopes. [Specimens since 

 found at the original locahty, and in the same layers, indicate a size 

 nearly twice as great as this.] 



"This may not be a Turritella, the specimens not being in a condition 

 to show the texture of the shell or to give a clear idea of its aperture 

 and lip. It would be a rather small species for that genus, and if it pos- 

 sessed the dehcacy of surface seen in those genera, it might perhaps with 

 more propriety be referred to Aclis or Ilenestho. The fractured lip in 

 some of the specimens has somewhat the appearance of a slight angu- 

 larity or very small notch at the base of the aperture, but this may be 

 due to the manner in which it is broken ; if not, it would seem to pre- 

 sent affinities with the genus Mesalia. It will be readily distinguished 

 from the species I described under the name T. spironema by its less at- 

 tenuated form and finer and less distinct revolving lines. It is also not 

 nearly so attenuated toward the upper part of the spire as that species. 



^'■Locality and position. — CoaMlle, Utah, from the Cretaceous below 

 the heavy bed of coal mined at that place." 



Genus EULIMELLA Porbes. 



EULEMELLA'? FUNICULA Meek. 



Plate 9, fig. 10 a. 



Bulimafunicula Meek, 1873, An. Eep. U. S. Geol. Sur. Terr, for 1872, p. 506. 

 fEulimella funicula White, 1876, U. S. Expl. and Siirv. West of 100th Merid. vol. iv, 

 p. 197, pi. xviii, fig. 6. , 



" Shell subterete or elongate-conical ; spire regularly tapering from 

 the middle of the body- volution to the apex, or with very sMght convex 

 slopes ; volutions about twelve, flattened ; last turn not much enlarged, 

 subangular around the middle ; suture merely linear; aperture ovate or 

 rhombic-subovate ; inner lip slightly thickened and reflected. Surface 

 smooth. 



" Length, 0.65 inch; breadth, 0.20 inch; divergence of slopes of spire, 

 about 19^. 



" This shell has much the appearance of a slender Msso, but it cer- 

 tainly wants the umbilicus seen in that genus, its axis not being iu the 

 sUghtest degree perforated. It is even more like some recent species of 



