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Show 352 crop out aloug the slope of the mountain, while reddish and yellowish ripple- marked sandstones compose the upper part of the same. Below the limestone, he saw exposures of a whitish fine sandstone, hand specimens of which closely resemble examples of the Potsdam sandstone brought by Dr. Hayden from the Black Hills and several localities along the Rocky Mountains, where that rock is known to be immediately overlaid by Carboniferous limestones. Fossils are apparently rare in this Carboniferous limestone, near the line of the bouudary survey, where they are usually so firmly imbedded in the hard brittle matrix that no specimens were procured in a condition to show very clearly their specific characters. Those collected consist of a small Zaphrentis, a Spirifer allied to 8. Keokuk, a small Athyris apparently uu distinguish able from A. subtilita, and a large Productu* agreeing nearly with P. latwimus, Sowerby. From these fossils, we can safely refer this rock to the Carboniferous system, and even with some degree of confidence, to the lower or Mountain Limestone series of the same. It is true, AthyHs mbtilita is generally, in this country, regarded as a Coal- Measure species; but we have a form in the Lower Carboniferous series of the Mississippi Yalley. scarcely distinguishable, which is even by some regarded as a variety of A. subtilita ; while Mr. Davidson identifies that species in the Lower Carboniferous rocks of England. Spirifer Keokuk and Productu* latis-simus are both Lower Carboniferous species, while the latter is very unlike any of our known American Coal- Measure species. • In its litho-logical characters, the matrix containing these fossils likewise agrees well with beds in the region of the Great Salt Lake containing Lower Carboniferous fossils, and apparently the same 8pirifer mentioned above; while it is quite unlike any of the known beds of the Far- West that can be certainly referred to the Coal- Measures. The presence here of Carboniferous rocks would seem to lend at least some encouragement to the hope that true coal of Carboniferous age may be found at some place along the Rocky Mountains farther south, near the line of the North Pacific Railroad. A few fragments of apparently Carboniferous or possibly Devonian fossils were also found on a small tributary of Fraser River, about fifty miles from the Gulf of Georgia. They occur in a dark, very hard, partly metamorphosed limestone, and consist of crinoid columns, and a portion of a large Zaphrentis. The crinoid columns have been dissolved out, and the cavities subsequently filled with calcareous matter retaining the original form, but not the structure of the fossils. Some of the columns measure as much as 0.80 inch in diameter, and show by the constrictions in the comparatively large central cavity some fourteen or fifteen segments in the space of an inch. The Zaphrentis, when entire, must have measured about 2£ inches in diameter at the larger end, being nearly as large as the Devonian Z. gigantea, though proportionally shorter, more abruptly tapering, and apparently more curved. None of these specimens, however, were in a condition to be figured. The Cretaceous fossils contained in the collection are from two localities on Vancouver's Island, and in part from Sucia Islands in the Gulf of Georgia. Those originally sent to the Smithsonian Institution were all from Vancouver's Island, and at the time they wese examined, by the writer, were supposed to have been all obtained from one locality, though we now know that they came from two distinct localities. They gave evidence, in the nature of the matrix, however, as well as in the species, of having been obtained from two different beds or rocks, one of which was unhesitatingly referred to the Cretaceous epoch. The specimens |
