276 Mr. S. V. Wood on the Form and Distribution of the 



they do under nearly the same latitude, this coast-line being what 

 I have termed the northern shore of the great nummulitic gulf. 

 It is worth observing, also, that such an identity of forms at so 

 great a distance is, so far as I know, unexampled during other 

 tertiary epochs (although it is conspicuous during the palaeozoic 

 period), and can hardly have existed, except by virtue of a simi- 

 larity of conditions over the whole area and of easy communica- 

 tion by coast-line. M. Abich also describes the older tertiaries 

 of the valley of the Araxes as containing a large proportion 

 of the species of the mollusca common to corresponding hori- 

 zons of the Paris basin, and, intermingled with them, many species 

 agreeing with mollusca from India described by M. d'Archiac*, 

 and containing also well-known forms of nummulites cha- 

 racteristic of the Pyrenean and other South-European num- 

 mulitic deposits. The proportion of the mollusca in the beds of 

 the Araxes valley common to the older tertiaries of England, 

 France, and Belgium is not so large as in the case of the beds 

 of the Aral-Sea region; but the intermixture of Indian species 

 much assists the proof of the continuous extension of the num- 

 mulitic gulf in the form I have described. The contiguity of 

 the Aral- Sea region to the northern coast-line of the gulf (which, 

 beginning perhaps to the north of the Indian beds described by 

 M. d'Archiacj-j extended to the Aral region at the extremity of 

 the Oural chain, and thence to England) would account for the 

 somewhat larger per-centage there of the shells of the basins of 

 North- Western Europe. The beds of the Araxes valley, on the 

 other hand, appear to have occupied a position more towards the 

 centre of the gulf, in the vicinity of insular land (formed by the 

 palaeozoic plateau of that region which is uncovered by eocene 

 deposits), but remote from the great coast-lines. The extra- 

 ordinary range of the mollusca of the older tertiary period over 

 the region filled by this sea tends, moreover, to show that the 

 sea-bed formed by the submergence of the post-cretaceous con- 

 tinent — a continent which I have suggested was a vast tract 

 uninterrupted by great mountains — was shallow over its whole 

 area, the tertiary mountain chains of Southern Europe and 

 South-Western Asia, which have since elevated portions of its 

 bed into land, and deepened other portions into the Caspian, 

 Black, and Mediterranean Seas, not having come into existence 

 until a later date. 



While we have thus evidence of a great gulf or land-girt sea 

 stretching, at the dawn of the tertiary period, from the Bay of 

 Bengal in a north-westerly direction to the British Isles, fringed 



* Animaux fossiles du terrain Nummulitique de VInde. Paris, 1853. 

 t These beds are, Hala in Scinde, the Cashmere valley, and the range 

 of Subathoo (part of Himalayan chain). 



