REVIEWS 195 



The new types described from this stage are Sphenopteris Ralli, S. 

 heracleensis, Potoniea adiantiformis , Calamophyllites vaginatus, Phyllo- 

 theca Ralli, and Sigillaria euxina. 



All but six of the species listed above are present in one or more of 

 the European basins. The flora of the lower horizon is referred to the 

 lowest of the three stages of the Westphalian, while that of the slightly 

 younger horizon is regarded as overlapping on the lower or transition 

 portion of the middle stage. 



It is impracticable to discuss in this place the relations of the large 

 and interesting flora from this stage to the floras of the United States. 

 I have, however, marked with the asterisk (*) those species that are 

 recorded from the Carboniferous of North America. 



The percentage of identical species is undoubtedly fully as large as 

 that marked in the list. Of the American representatives among the 

 fern species the greater portion are present either in the Kanawha for- 

 mation of southern West Virginia and Kentucky, or the upper portion 

 of the Pottsville formation. In fact the flora of the lower horizon in 

 the Coslou group is clearly comparable to the topmost Pottsville and 

 earlier Kanawha plant associations. The flora of the upper horizon of 

 the Coslou group has little in addition besides the Sigillarias that is 

 common to the Allegheny series, and it, too, is distinctly older than that 

 series, though it appears hardly so typical as the other flora of the Lower 

 Kanawha group. The surprisingly close relations of the flora of the 

 Coslou stage to the uppermost Pottsville, and particularly to the Lower 

 Kanawha flora will be better understood when the detailed studies of 

 the latter floras are published. Suffice it for the present to say that 

 the species marked by the (f) in the above list are, so far as I have 

 observed, peculiar to and characteristic of this combined portion of 

 the Appalachian Upper Carboniferous section. 



A few among the more important species closely related to Ameri- 

 can types deserve special mention : Sphenopteris Vullersi is very close 

 to a variety of S. furcata from the Southern Anthracite field ; .S. Stern - 

 bergi to Aloiopteris {Sphenopteris) georgiana of the Pottsville ; and Ale- 

 thoptcris Davreuxi differs but little from the latest phase of A. grandi- 

 folia. My remarks on the Lepidophyllum lanceolatum in the lower stage 

 probably apply equally to the Coslou specimens. 



iVs Potoniea Zeiller describes a type of fructification whose fleshy 

 adiantiform divisions are studded or fringed with fusiform bodies sug- 

 gesting the sporangia of Crossotheca [Sorocladus of Lesquereux). It is 



