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clusively cover patches of many square yards. This was over a 

 distance of two miles along the ridge, along the western edge of 

 the burned area, well within the area, and along its eastern and 

 southern edges. The spores might possibly have been trans- 

 ported from small colonies along a brook emptying Tock's 

 Swamp, which was so wet that it escaped burning, outward a 

 few rods, and have started new thalli on the bare burned soil, 

 but it seems surprising that the crop of spores of the summer and 

 early autumn of 1930 from plants in limited areas should have 

 produced such extensive new growth by autumn of 1931. There 

 was a rainy spell about a month after the fire and the charred 

 soil was well wetted, which probably helped the Marchantia 

 spores to germinate and develop new thalli. But that this ex- 

 tension should have covered many acres of the burned land, at 

 elevations 10 to 300 feet above the previous possible occurrences 

 of the hepatic in the swamp, within so short a time, seems an 

 astonishingly prolific development. Yet Mr. Diehl's observa- 

 tions on Old Rag Mountain in Virginia indicates a similar phe- 

 nomenon. How did the elaters carry the spores upward as seems 

 to have occured. There can scarcely be any accidental transpor- 

 tation by animals, birds, or insects, over such distances from the 

 swamp. The Marchantia colonies grew all over the burned area, 

 which was three miles long and two miles wide. Nearly every- 

 thing above ground outside of the swamp was killed. Yet the 

 tiny spores of this hepatic survived in the swamp and soon after 

 the blaze it was the first new plant to take over the black ashes. 



Hollis, New York 



