46 THE CARBONIFEROUS. 



its equivalents. In the following lists I have given the equivalents 

 of the Horton series and Millstone-grit series as they appear to me 

 to be settled by stratigraphy and fossils : — 



1. Equivalents of the Lower Carboniferous Coal-Measures or 



Horton Series. 



(1.) The Vespertine Group of Rogers in Pennsylvania. 



(2.) The Kinderhook Group of Worthen in Illinois. 



(3.) The Marshall Group of Winchell in Michigan. 



(4.) The Waverley Sandstone (in part) of Ohio. 



(5.) The Lower or False Coal-measures of Virginia. 



(6.) The Calciferous Sandstones of M'Laren, or Tweedian Group 



of Tate in Scotland.* 

 (7.) The Carboniferous Slate and Coomhala Grits of Jukes in 



Ireland. 

 (8.) The Culm and Culm Graywacke of Germany. 

 (9.) The Graywacke or Lower Coal-measures of the Vosges, as 



described by Schimper. 

 (10.) The Older Coal Formation of the Ural, as described by 



Eichwald. 

 (11.) The so-called " Ursa Stage" of Heer includes this, but he has 



united it with Devonian beds, so that the name cannot be 



used except for the local development of these beds at Bear 



Island, Spitzbergen. 



All of the above groups of rocks are characterized by the preva- 

 lence of Lcpidodendra of the type of L. corritgatum, L. Velthei- 

 mianum, and L. Glincanu?n, and also of the type of L. tetragonum of 

 Sternberg (Bergeria of some authors),-]- pines of the sub-genus Pitus 

 of Witham, Palwoxylon of Brongniart, and peculiar ferns of the 

 genera Cyclopteris, Cardiopteris, and Sphenopteris. In all the regions 

 above referred to they form the natural base of the great Carboniferous 

 system. 



* Some attention has recently been given to these beds in England and Scotland 

 by Geikie, Hull, Lebour, and others, and new names have been proposed, as that of 

 " Valentian" by Geikie. The name " Tweedian " of my old friend Tate should, I 

 think, stand. Many years ago, when I was engaged in the study of these rocks, he 

 seemed to be the only English geologist who knew much about them. Of late years 

 much confusion has been introduced into the geology of these beds by some Euro- 

 pean palaeo-botanists. Stur has, however, worked up their fossils in Silesia, as Eich- 

 wald had done in Russia, and in both regions they correspond very closely with the 

 flora which I have found in Nova Scotia, and have described in the Report above 

 referred to. Meek has also recognised this flora in Western Virginia. 



f This type of Lepidodendron has been recognised even in Australia, but seems 

 there to be referred to the Devonian age. 



