353 



from the other bed at Nanaimo being, so far as determined, all new spe- 

 cies, and belonging' apparently to genera common to the Cretaceous and 

 Jurassic systems, some doubts were entertained whether or not they 

 might belong to the latter ; though it was stated tliat from their general 

 characters and aiEnities, it appeared mere probable that they belonged 

 also to the Cretaceous. On looking them over some time after, however, 

 the writer was led to suspect that they might be of Jurassic age, which 

 suggestion was mentioned to Dr. Newberry, who referred to it in his 

 report on the geology of Captain Williamson's Pacitic Eailroad Survey. 



A review of the whole subject, however, with the aid of the additional 

 light derived from the more extensive collections brought in by the 

 Northwestern Boundary Survey, fully confirmed the original conclusion 

 that the whole belong to the Cretaceous. One of the strongest evidences 

 of this is the occurrence, in these beds at Nanaimo, of numerous dico- 

 tyledonous leaves,of so modern an aspect that some who have examined 

 these leaves alone, without regard to the associated molluscan remains, 

 have even thought that these beds ought to be referred to the Tertiary. * 

 That they do not belong to the Tertiary, however, is evident from the 

 fact that they also contain a large species of Inoceramus and a Goniomya^ 

 together with Cretaceous types of Trigonia and Fholadomya. 



The Nanaimo locality is on the eastern shore of Vancouver's Island, 

 and Komooks, or Komax,t which is also on the eastern shore of the 

 same, is about sixty to seventy miles farther northwest ; while the 

 Sucia Islands are in the Gulf of Georgia, abont the same distance in a 

 southeast direction from Nanaimo. At the Nanaimo locality, the beds 

 consist of sandstone, good coal, and conglomerates, composed of small 

 pebbles, with seams of greenish-gray and brownish beds of arenaceous 

 matter containing fossils, the whole dipping eastward. Tiie same beds 

 also occur on the neighboring Douglass and New Castle Islands, where 

 they likewise contain coal. These beds seem to be quite distinct from 

 those at Komooks and on Sucia Islands, both in their fossils and in 

 their lithological characters ; and from the affinities of their fossils, as 

 as well as from the direction of the dip of the strata, I am inclined to 

 believe them older than those seen on the Suica Islands and at 

 Komooks, though the whole seems to belong to division A of the 

 California reports. The Nanaimo beds do not seem to be equivalent 

 to any of the subdivisions recognized in the Upper Missouri country. 



The Komooks and Sucia Island beds, however, appear, both from the 

 affinities of their fossils, and from the state of preservation of the latter, 

 to be related to what we have called the "Fort Pierre group", or divis- 

 ion No. 4 of the Upper Missouri section. In the latter district, this 

 division is composed mainly of dark plastic and indurated clays, in 

 which the fossils often occur enveloped in hard concretions, and show 

 the substance of the shells in a beautiful state of preservation. Those 

 from Komooks and Sucia Islands are in a similar state of preservation, 

 and appear to have been enveloped in similar concretions; while the 

 specimens from Nanaimo are mainly casts, or, where they retain any 

 portion of the shell, it is more decomposed and has an older look. 

 Among the species from Komooks and Sucia Islands, some of the Bacu- 

 lites and a Kautilus are related to species found in No. 4 of the Upper 

 Missouri, while one of the Ammonites and one of Inoccmmus appear 

 scarcely to differ more than as varieties from forms found in the horizon 

 mentioned in the Upper Missouri, 



* These plant-remains have been iuvestigated by Dr. dewberry, and by him referred 

 to the Cretaceous. 

 t Mr. Gabb -svrites this name " Komax '' in the California report. 



