Rocky Mountains. 151 



ty arrived from the Oto village, whither he had been sent 

 with a deputation of Konzas, to aid in effecting a reconcilia- 

 tion between those nations. This proposition, which origi- 

 nated with the Konzas, was favorably received by the Ot- 



25. A single specimen was found of a valve of a shell, in some degree 

 resembling a pecten, but without the auricles. Length, more than 2 3-10 

 inches. 



26. Productus lineolatus. Say. Valves with numerous, fine, equal, 

 equidistant, longitudinal strite, and a few small tubercles; convex valve 

 very much elongated, its basal portion is curved downwards, almost per- 

 pendicularly with respect to the disk near the umbones. 



Su singular is the structure of this shell, that the internal cavity appears 

 to have been perfectly transverse, with respect to the general length of the 

 shell, and small in comparison with the length. It stroiigly resembles the 

 Anomites productus of Martin, as represented on plate 22, fig. 102, of his 

 Pctrif. Derbi., and like that shell it is armed with small tubercles, though 

 fewer in number, and the strite are much more numerous and smaller. 



27. Cast of a turretted univalve, probably a Cerithium, of the length of 

 2 1-2 inches. 



28. t.ast of the anterior portion of a valve of a shell like an Ostrea, of 

 the breadth of 2 1-2 inches. 



29. On the Missouri near the Platte, occur masses of rock, which seem 

 to be almost exclusively composed of a remarkable petrifaction, belonging 

 to the family of concamerated shells. This shell is elongated, fusiturm, 

 and when broken transversely, it exhibits the appearance of numerous 

 cells disposed spirally as in the Nummvlite, but its longitudinal section 

 displays only deep grooves. The shell was therefore composed of tuoes or 

 syphons, placed parallel to each other, and revolving laterally as in the 

 genus jilelonis of Lamarck, with which its characters undoubtedly cor- 

 respond. But as in the transverse fracture, its spiral system of tubes 

 cannot be traced to the centre in any of the numerous specimens we 

 have examined, it would seem to have a solid axis, and consequently belongs 

 to that division of the genus, that Montfort regards as distinct, under the 

 name of Miliolites, which seems to be similar to the Fasciolites of Parkin- 

 son, and altogether diffeient from the Miliolites of Lamarck. Our speci- 

 mens are conspicuously striated on the exterior, which distinction, toge- 

 ther with their elongated fusiform shape, sufficientl) distinguish them as a 

 species from the sabulosus, which Montfort describes as the type of hisgenus. 

 No aperture is discoverable in this shell, but the termination of the exte- 

 rior volution, very much resemlles an aperture as long as the shell. 



The length is three-tenths of an inch. And its greatest breadth, one- 

 twelfth. 



We call it Miliolites secalicus. Say- Mr. T. Nuttall informs me, that 

 he observed it in great quantities high up the Missouri. 



In the same mass were some segments of the Encrinus, and a Terebra- 

 tula with five or six obtuse longitudinal waves. 



30. Another petrifaction, abundantin some fragments of compact carbon- 

 ate of lime, also found on the shores of the Missouri, possesses all the generic 

 characters, which we have attributed to the preceding species, excepting 

 (hat in the transverse fracture, the cells distinctly revolve from the oen- 



