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portions of it at least — emerged from the sea. An alternative 

 hypothesis would be that C. nudata was evolved from C. virgala 

 at a comparatively recent period, geologically speaking, and being 

 in some manner adapted to a widespread habitat became widely 



Fig. I. Ledge of Altamaha Grit on west side of Rock Hill, Florida. Chon- 

 drophora virgala is common on top of these rocks. 



distributed. This however does not account for the remarkably 

 disjointed distribution of C. virgata, unless we ascribe to it 

 extraordinary facilities for dissemination. Evidently there are 

 some unknown historical factors still to be taken into considera- 

 tion. 



The known distribution of Chondrophora virgata may now be 

 summed up by saying that it is known from three counties in the 

 mountains of Alabama, four in the coastal plain of Georgia, and 

 one in West Florida, always on non-calcareous rocks. (I have 

 seen it myself in all these eight counties, and have collected it 

 in half of them.) The re-discovery of the long-lost stations in 

 Louisiana and Texas is greatly to be desired, especially in view 

 of the fastidiousness of this plant as to habitat. It would appear 



