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ELISHA MITCHELL SCIENTIFIC JOURNAL 



they occur have the same general character as the specimens 



Mil 



These from Chapel Hill 



from the Sam Christian 

 smaller and the definite Palaeotrochis form not so abundant 

 among- them. Microscopical study shows that they are com- 

 posed of quartz, fibrous feldspar, and mica * usually green 

 biotite), just the minerals common in the igneous rocks 

 around Chapel Hill. These studies indicate the inorganic 

 origin of Palaeotrochis. 



Secondary Radiation from Thorium Compounds. Geo. B. 

 Pegram, New York. 



The following papers were read by title: 



The Flora of the Isle of Palms. South Carolina. W. C. 

 Coker. Chape/ Hill. I Abstract . 



The flora of this island, which is near Charleston, is semi- 

 tropical in character and presents an interesting transition 

 between that of the Florida and North Carolina coasts. The 

 island is entirely formed of wind-blown sand and its seaward 

 side is furnished with high dunes which offer good advan- 

 tages for the study or the binding action of grasses and the 

 dune plants. 



Twenty-seven species of grasses were found, five of which 

 also occur in the Bahama Islands. 



Thirteen species of trees and twenty-rive of woody vines 

 occur; the most abundant trees being the Palmetto (Sabal 

 Palmetto i. Live Oak (Quercus virens), Laural Oak I Ouercus 

 Jaurifolia) and the Old Field Pine | Pinus taeda >. Photo- 

 graphs were taken of various plant associations. 



Theory of the Induction Coil. C. W. Edwards, Durham. 



The Granville Tobacco Wilt. F. L. Stevens and IF. G. 

 Sackett. Raleigh. 'Abstract . 



A new tobacco disease which is exceedingly destructive is 

 recorded for Granville County. The disease is described, the 

 extent of the damage estimated, and its history and distribu- 

 tion given. 



The diseased plants in the effected parts of the root and 



