96 GEOLOGICAL SURVEY OF THE TERRITORIES. 



teresting portion of this group of plants, and all seem to be quite distinct from the 

 fossil species hitherto described, or any now living. Of our American sycamores, the 

 leaves of P. occidentalis are much more toothed, while those of P. racemosa are more 

 deeply lobed than any of these. P. aceroides, a species from the tertiaries of Europe, is 

 more closely allied to our living ones than these seem to be. The largest and finest of 

 those now described (P. nobilis,) in its smoothness of surface, crowded and parallel 

 nervation, departs more widely from the typical species of Platanus than the others, 

 and has more the appearance of a tropical plant. An extensive series of comparisons 

 has, however, suggested no affinities closer than those with the living Platanus, and 

 I have little doubt that in these leaves, of which the collection contains a large num- 

 ber; we have representatives of the noblest and most beautiful species of the genus. 



Two of the species of Corylns present no characters by which they can be distin- 

 guished from the two now distributed over the temperate portions of our continent ( C. 

 rostrata and C. Americana,) and I have, therefore, not felt justified in considering them 

 distinct. The Carya, figured, seems to me clearly to belong to this genus, and to be 

 closely allied to one of our living species. The Tilia also is not far removed from T. 

 heteropliylla, one of our southern living species ; while the Negundo, Sapindus, &c, seem 

 to be the representatives of the genera and species now growing near the regions from 

 which these fossils come. 



From this flora, considering it the analogue and progenitor of that which now occu- 

 pies our territory, we miss some important elements, and such as we may confidently 

 expect will be supplied by future collectors. Among the most striking of these 

 deficiencies may be mentioned Acer, Querents, Magnolia, Liriodendron, Liquidambar, Sassafras 

 &c., some of which, as we know, began their life upon the continent during the creta- 

 ceous period, aud all of them were members of the miocene flora of the Old World. 

 Liquidambar, Quercus, and Magnolia occur in the pliocene beds of New Jersey, Magnolia 

 and Quercus in the miocene strata of the Mississippi Valley; Fagus also, which is want- 

 ing in the collection, has been obtained from the eocene by Mr. Lesquereux. 



On comparing this flora with that of the miocene rocks of the west coast, we find 

 Smilax, Quercus, Salix, Oreodaphne, Acer, and Cinnamomum — all of which are represented 

 there — to be wanting here, while the Sabal, Glyptosirobus, and Taxodium are common to 

 the two floras. 



Until further collections shall be made from the plant beds of the Upper Missouri, it 

 is evident that the deductions from the negativo evidence of absent genera and species 

 must be regarded as unsatisfactory, but it is a fact, not without its significance, that 

 the genus Cinnamomum, which was largely represented in both the cretaceous and ter- 

 tiary deposits of the west coast, and in the eocene of the eastern portion of the conti- 

 nent, should be entirely absent from the large amount of material collected by Dr. 

 Hayden.* 



We are at least justified in saying that from the evidence now before us, wo must 

 conclude that the flora of the banks of these inland lakes of the miocene period was 

 that of a temperate climate, not warmer than that of the middle portion of our South- 

 ern States, and somewhat less warm than that of the eastern portion of our continent 

 during the eocene period, or the western during the miocene age. 



The notes on some of the species contained in the collection made by Dr. Hayden, 

 Sequoia Langsdorfii, Sabal campbellii, Onoclea sensibilis, &c, have a bearing on the general 

 questions to which reference has been made in the preceding pages, but the occurrence 

 of an Onoclea among these miocene plants, and a species which I cannot distinguish 

 from the living one, seems to me a fact of so much importance as to require some addi- 

 tional comments. 



The fern frond found by the Duke of Argyle in the leaf beds of the Island of Mull, 

 and figured by Professor E. Forbes in the Journal of tlie Geological Society of London, 

 (vol. vii, 1851, p. 103 ; PL II, Figs. 2a, 2b,) and named by him Felicites (?) hebridicus, is 

 unquestionably identical with this. The specimen from which the figures I have re- 

 ferred to were taken seems to have puzzled Professor Forbes somewhat, for he doubted 

 if it was a fern ; and Professor Heer, in his reference to the fossil plants of the Island 

 of Mull, (Flor. Tert., Helvet., vol. iii, p. 314,) says: "The most remarkable species is 

 Felicites (?) hebridicus, a fern which by its nervation differs greatly from those of the 

 continent." All these facts give this fossil special interest, for, in addition to its rela- 

 tions to its living representatives — of which we cannot but consider it the progenitor — 

 it adds another to the list of plants common to the miocene strata of Europe and 

 America. 



Of these — either representative or identical species — the number is now so great that 

 they plainly indicate a land connection between the continents at that period ; and 

 since many genera, and this, with probably some other species, at that time common 

 to the Old and New Worlds, have disappeared from Europe while they continue to 

 flourish here, it would seem to follow that these were American types which had colo- 



*If it is true, as now seems probable, tbat a large part of the Bellingham Bay deposits are cretaceous, 

 that would account for this marked difference between, the plants collected by Dr. Evans, Mr. Gibbs, 

 &c, from those collected by Dr. Hayden. 



