GEOLOGICAL SURVEY OF THE TERRITORIES. 499 



same matrix,) I find a single small individual, sliowing very obscure 

 traces of radiating- brotvu stripes, like those occurring between the costte 

 of the last, (the other specimens not being in a condition to preserve 

 marks of color.) It is possible, however, that this smaller individual, 

 showing traces of colored stripes, may be distinct from the others. It 

 would be rather remarkable if this and the last described species should 

 be the same, since an interval of about 600 feet of strata occurs between 

 the beds in which they were found; while all of the other species, so 

 far as known, from the two horizons, are distinct, and no shell resem- 

 bling these forms is known to occur in any intermediate horizon. 



Locality and position. — Coalville, Utah, from the Cretaceous beneath 

 the lower heavy bed of coal mined at that i)lace. 



Neritina (Dostia?) carditoides, Meek. 



Shell attaining a moderately large size, broad, oval, and depressed in 

 form, apex posterior, and nearly or quite depressed to the margin, appar- 

 ently obliquely subspiral ; inner lip very broad, or forming more than 

 half of the under side, rather thick, smooth, and nearly flat, or some- 

 what convex, with its straight inner margin sharp and without teeth 

 or crenulations; outer lip thick, very obscurely crenate within, and 

 apparently continuous with the margins of the inner one around be- 

 hind; aperture transversely semicircular, and less than half the size of 

 the under side of the shell. Surface ornamented by about fifteen simple, 

 narrow, sharp, and snbcrenate radiating costro, separated by wider, 

 rounded, intermediate furrows ; lines of growth distinct. 

 . Length, about 0.87 inch ; breadth, 0.70 inch; convexity, 0.35 inch. 



This is another curious form allied to the little si)ecies I have described 

 nnder the name N. hellatnla. When viewed from the dorsal side, as 

 seen lying with the aperture downward, its form and strong radiating 

 costai give it much the appearance of the left valve of a Cardita or Car- 

 diiun. The only specimen of it in the collection has its apex and poste- 

 rior and lateral margins broken away, and its broad, smooth, shelf like 

 inner lip broken by pressure inward. Still, however, it gives a tolera- 

 bly correct idea of the characters of the shell. In several respects it 

 agrees with Vclates, and possibly might, without impropriety, be called 

 Velates carditoides. 1 suspect, however, that when better specimens can 

 be examined, it will be found typical of an undescrbed section, including 

 also the little species N. bcUatula. If so I would propose for the group 

 the name Velatcila. I know of no nearly allied described type. 



Locality and position. — Carleton's coal-mine, Coalville, Utah. Creta- 

 ceous. 1 am under obligations to Mrs. Carleton, the wife of the gentle- 

 man who owns the coalmine at w hich the specimen was found, for the 

 only example of the species I have seen, which was discovered by her 

 while we were at the locality. 



Neritina (Neritella) Bannisteri, Meek. 



Shell subglobose; spire much depressed, or with its apex scarcely 

 rising above the body whorl; volutions three to four, rapidly increasing 

 in size, so that the last one comprises nearly the entire shell, more or 

 less flattened, and sometimes provided with an obscure linear revolving 

 furrow above; aperture large, subovate, approaching semicircular, being 

 a little straighter on the inner side ; outer lip beveled to a thin edge; 

 inner lip of moderate breadth, slightly concave, and flattened, with a 

 Bteep inward slope, entirely smooth. Surface polished, and marked by 



