No. XV. GEOLOGY. 331 



could not be determined, it is doubtful whether these rocks 

 represent the ' Ursa stage' of Heer, and whether they form 

 the base of the carboniferous limestone. Should it be even- 

 tually proved by future researches that the ' Ursa stage ' is 

 absent, it would appear probable that these beds were 

 only deposited further south. 



The rocks lying above the Silurian limestone of the 

 Arctic Archipelago occur in a synclinal trough or hollow, 

 ranging W.S.W. and E.N.E. from Banks Land through the 

 Parry Islands. At Byam Martin Island, M'Clintock describes 

 two sandstones, the one red, finely stratified, associated with 

 purple slate, resembling the red sandstone of North Somerset, 

 Cape Bunny, and that found between Wolstenholme and 

 Whale Sounds, W. Greenland ; and another, fine-grained, 

 greyish-yellow coloured, resembling the coal-bearing sand- 

 stone of Cape Hamilton, Bank's Land (Baring Island). It 

 contains numerous casts of a brachiopocl, allied, according to 

 Dr. Haughton, to Terebratula (Atrypa), primipilaris, Von 

 Buch (and to A. fallax of the carboniferous rocks of Ireland), 

 found abundantly at Grerolstein in the Eifel, now known as 

 Mhynchonella primipilaris. Associated with these later 

 sandstones are coal-seams striking E.N.E. to Bathurst Island. 

 The coals have a lignaceous texture, consisting of thin layers 

 of brown coal and jetty- black glossy coal, with a wooden ring 

 under the hammer. 



The identity of genera and of some species of the flora of 

 the pre-carboniferous limestone 6 Ursa stage ' with those of 

 the rocks of Europe, lying immediately above the limestone, 

 point to the equable and identical climate prevailing over 

 very large areas of the earth's surface, and to the local and 

 temporary character of the deep sea conditions expressed by 

 the formation of the mountain limestone, in the midst of a 

 long continental episode, marked by the first rich land flora, 

 in the earth's history, which can be traced both in the old world 

 and in the new, from 47° to 74° and 76° north lat., and which 

 was as fully developed beyond the Arctic Circle, as in Central 

 Europe : the leaves of the evergreen tree Lepidodeiidra, and 



