Hayilen.] "^^^ [May a, 



pressed laterally, and a little excavated, without being distinctly chan- 

 neled on each side of the ventral keel ; inner ones but slightly embraced 

 by each succeeding turn, and consequently vfcU exposed in the wide umbili- 

 cus. Surface ornamented with numerous unequal costse, some of the larger 

 of which bear a small, somewhat pinched node near the umbilicus, and two 

 closely approximated small nodes around the ventro-lateral margins, 

 where they all curve very strongly forward as they pass upon the periph- 

 ery; spaces between each two of the large nodose costse, occupied by from 

 one to about three smaller ones. Septa unknown. 



Although undoubtedly a Cretaceous species, this shell would rather 

 nearly resemble A. spinulatus, Brug., from the Lias, as illustrated by 

 d'Orbigny, if that species had from one to three smaller costse between 

 each two of its ribs, and its serrated keel more prominent. Our shell also 

 differs in the presence of a small node near the umbilicus, on each of the 

 larger costse. It is not a true Ammonite, according to the latest classifica- 

 tion of the Ammonitidce. 



Fort Bascotn. 



28. OrypJicea navia, Conrad. Cret. No. 2 or 3. 



Bodsoii's Banclie. 



29. Inoceramus proMematicus, Schloth. (sp.) Cret. No. 2. 



30. CucuUcea, andf other undt. hivalves. " " 



31. Anchura, undt. " " 



Como — (C. L. Morchom). 



32. Baculites ovattis, Say. 



J^ear Coahille, in high hill, and near base of same. 



33. Ostrea (undt. sp.) 



34. Modiola Pedernalis, Roemn. 



35. Nuculana. 



36. Pleurotomaria ? ? 



Tertiary Species. 

 Associated witJi Goal-bed, Bear Biver City. 



1. Ostrea soleniscus, Meek. 



Attaining a length of near one foot, and very narrow, or not more than 

 from one to two inches in breadth ; almost perfectly straight, excepting 

 the immediate beaks, which usually curve a little to the left ; sides nearly 

 straight and parallel. Upper valve flat ; lower moderately concave, and 

 like a little trough. Surface of both valves without radiating strise or 

 costse, or strong concentric markings. May be Cretaceous. 

 Limestone-Mil, Bear Riiier. 



2. TJnio vetustus, Meek. 



3. Unio helliplicatus, Meek. 



Differs from the last in having the posterior dorsal region marked with 

 about six to eight strong, regular, oblique plications, which begin very 

 small and crowded, just in front of the beaks, and radiate backward and 

 downward nearly to the posterior and postero-basal margins. 



