GEOLOGICAL SURVEY OF THE TERRITORIES. 501 



ever, and tbns enabled me to see tbat it is denticulated, and in tbis 

 respect differs from Neritina pisuni, wbicb seems to be entirely witbont 

 teetb. Fiirtber compaiisous also sbow tbe two sbells to differ in form, 

 tbat nuder consideration bavin|r a more prominent spire and a more 

 globose outline, being less oblique. 



Tn size and general appearance it also closely resembles small exam- 

 ples of Neritina compacta, Forbes, from tbe Cretaceous rocks of India; 

 but it is less oblique, or more globose in form, and bas four denticles 

 instead of only tbree on its columella. It is possible I sbould call it 

 Ncrita pisijormis, as tbe denticuiations of its columella are ratber 

 strongly developed i'oraNeritinay in wbicb genus tbe columella is usually 

 sniootb, or only finely crenate. Its general aspect, bowever, is more like 

 species of tbe latter group. 



LncaJitij and poxition. — Coalville, TJtab, from tbe Cretaceous beds 

 below tbe beavj- lower bed of coal mined tbere. 



Adimete! RHOMBOiDES, Meek. 



Sbell ratber small, rbombic suboval, or sbort subfusiform, tbe lengtb 

 being sligbtly more tban twice tbe breadtb at tbe widest part, wbicb is 

 near tbe middle; spire ratber depressed-conical, subturreted ; volutions 

 five or six ; convex ; last one forming about tbree-fourtbs tbe entire bulk 

 of tbe sbell, and more tban balf of its lengtb, widest near its upper part, 

 and abruptly narrowed below so as to present an obliquely obovate 

 form ; suture ratber deep from tbe convexity of tbe volutions ; aperture 

 narrow, subangular above and narrowed below to a small notcb at tbe 

 base of tbe truncated columella, wbicb is provided witb two small obscure 

 plaits or folds, tbe b^ver of wbicb is formed by tbe twisted margin of tbe 

 truncated inner lip, wbile tbe otber is placed a little fartber up ; outer lip 

 sbarp, witb its margin sligbtly retreating above, and more prominent 

 below, or near tbe middle. Surface ornamented by distinct vertical Iblds, 

 that are usually well developed on tbe volutions of tbe spire, and around 

 tbe upper part of tbe body wborl,but become obsolete below ; moderately 

 distinct revolving lines also mark the lower part of tbe body volution, 

 but tbese appear to become obsolete on its upper part, and on those of 

 tbe spire, as specimens are usually found. 



Lengtb, 0.37 inch; breadtb, 0.21 inch ; angle of spire about 58°. 



1 am much perplexed in regard to tbe proper disposition to make of 

 this and tbe first two of tbe lollowing species. In some of their charac- 

 ters, they would seem to be related to certain types of tbe Mitrhuv. such 

 as T^«<//jet»/f',Blainville, (= VuJpcctda^lLlQm ;) while in others they appear 

 to have aflinities to the CdnceUariidce, being much like the genus Ad- 

 mete. Without being at all satisfied, however, that they belong prop- 

 erly to the latter genus, T have concluded to refer them to it, provision- 

 ally, for the present, until better specimens can be obtained for study 

 and comparison. My present impression is, that they will prove not to 

 belong properly to any of the established genera, Mben all their charac- 

 ters can be clearly made out. If it should be found desirable, however, 

 to establish a new group for their reception, I would propose for it the 

 name Admetopsis, from the resemblance of the shell to the typical forms 

 of tbe genus Admete. 



Locality and jjo,s/7/o«. — Coalville, Utah. From Cretaceous beds be- 

 neath the lower heavy bed of coal at that place. 



Admete ? geegaeia. Meek. 



Shell small, oval, subfusiform ; spire moderately jirominent, conical, 

 and apparently terminating in a pointed ai)ex; volutions five or six, 



