416 PROCEEDINGS OF THE ACADEMY OF [May, 



there. " Timber was scarce on the tops of the Cniggies. There 

 was much pasture, and some of the red rhododendron. Wide 

 * balds,' but exceedingly rocky, the most mouutaiulike of anything 

 I have seen" (J. H. F.). After the return from Craggy, the 

 remainder of the time was spent in exploring Tyson's Cove. 



The Fauna. 



So far as the material before us affords a basis of judgment, it 

 goes to shovv: 



First— Thsit the French Broad river is not in itself the dividing 

 line between the Eoan and Smoky faunas. 



Second. — That in all probability there is no sharp line of de- 

 markation anywhere. But that in the intermediate region lying 

 between these faunal centres, the species peculiar to each mingle to 

 a greater or less extent, according as they find acceptable condi- 

 tions of environment. 



Third. — That in the French Broad river region there are a 

 number of 'peculiar forms which tend to show that it has, at least, 

 some of the characteristics of a distinct faunal ai^ea. 



Thus, in the species which inhabit the lower levels between the 

 mountains, and which may be considered as the cove fauna, we find 

 that the great majority are species common in the Appalachian 

 range along its whole extent. Occasionally, however, in these, 

 such as Polygyra tridentata and Pyramidula alternata, local races 

 are developed, which are eminently characteristic of the different 

 regions. 



In addition to these species of general occurrence, we find others 

 which are apparently restricted to narrower limits and which, with 

 the local races above mentioned, give these areas the peculiar 

 features, which taken in connection with the still more differenti- 

 ated elements occupying the higher levels, justify their separation 

 as distinct faunas, or rather faunulas. 



Taking the whole region from Roan to the Great Smoky moun- 

 tains into consideration, however, we find that so far as the cove 

 species are concerned, the differences are not so great as they 

 appear at first sight, and that in reality they are comparatively 

 small though sufficiently well marked. The only species peculiar 

 to the coves around Roan are the large and small forms of Polygyra 

 tridentata, Pyramidula hnjanti, Polygyra subpalliata and Ompha- 



