274- Mr. S. V. Wood on the Form and Distribution of the 



mountain systems of Southern and Central Europe and South- 

 Western Asia. The absence of deposits of a thickness sufficient to 

 withstand subsequent degradation during a period of elevation has 

 been urged by Mr. Darwin* ; and if true (as it may well be in the 

 sense of a general continental elevation, although not in that of 

 the gradual shoaling of such gulfs as those which received the 

 secondary deposits of France and England), we see in it an ex- 

 planation of the limited extent of the newest secondary (supra- 

 cretaceous) deposits, since it would only be on the skirts of the 

 continent formed out of the cretaceous sea-bed where these would 

 occur; and this skirt, except on its northern border, has not yet 

 been explored. The intra-cretaceous and tertiary deposits would, 

 I conceive, be taking place in the contiguity of any of the vol- 

 canic bands then in activity ; and we may still therefore look for 

 their discovery, unless they should now be beneath the ocean. 

 The Cordillera of the Andes, Mexico, California and Oregon, 

 places where, according to the views before discussed, the direc- 

 tion of the coast-line of America has remained since the secondary 

 period unaltered in its main features, and perhaps even Southern 

 India, offer probable sites for the occurrence of intra-cretaceous 

 and tertiary deposits j\ 



We have seen that the conformability between the newer 

 secondary and the tertiary formations, from the British Isles as 

 far east as India, shows that the tertiary sea over that area re- 

 turned mainly to the same bed as that occupied by the secondary 

 sea; it differed, however, essentially in one particular, viz. in 

 being shut in to the north by a barrier of land, no incon- 

 siderable portion of which was composed of elevated cretaceous 

 deposits : we find in the nummulitic deposits of Southern Europe, 

 Northern Africa, Southern and South- Western Asia, the evidence 

 of a vast gulf (interspersed with numerous islands) stretching 

 from the Bay of Bengal north-west through Hindostan and 

 Persia, across Asia Minor into Europe and North Africa, 

 including within it the present Mediterranean, Black, and 

 Caspian Seas; while, fringing the barrier of land which bounded 

 it on the north, we find the richly stocked marine deposits 

 of the English, Belgian, and French eocene basins generally 

 associated with estuarine and fluviatile beds of contemporaneous 

 age J. Fringing land composed of elevated Jurassic deposits, 



* Origin of Species, pp. 300 and 327. 



t I entertain considerable confidence that some of the beds associated 

 with the great lignite formation of North-Western America, California, and 

 Vancouver will eventually prove to be of intra-cretaceous and tertiary date. 



| The same association of fluviatile and estuarine beds with the num- 

 mulitic deposit seems to exist wherever an insular tract of land occurred in 

 this gulf — as in the Pyrenees, where remains of eocene mammalia have been 



