64 



Mycologia 



the winter weather of Missoula, Mont. ( — 30° Fahr.). In late 

 spring these plants revived and produced new fertile spore sur- 

 faces. These experiments not only illustrate the xerophytic nature 

 of the group^° to which they belong, but demonstrate the fact that 

 at least some tropical wood-destroying fungi will, no doubt, find 

 suitable conditions of growth in regions farther north. It may 

 be expected, of course, that the change in environment will afifect 

 certain morphological changes in the fruiting structure. Indeed 

 the question may be asked, why not regard Polystictus sanguineus 

 identical with P. cinnabarinus Jacq. This response to change in 

 environment may be observed in any of our native species in its 

 range from warmer and drier regions to the damp cold forests of 

 the north, or when observed at different elevations on high 

 mountains. 



As already indicated, there is always the danger of a fungus, 

 irrespective of the part of the world from which it may come, 

 finding a more favorable environment when introduced into new 

 regions. The history of many of our plant disease epidemics in 

 this country during the past few years illustrates this fully. It 

 is possible that certain of our common wound fungi may have 

 developed parasitic tendencies due to great difficulties to be over- 

 come, as has previously been indicated, and may be of some eco- 

 nomic importance in this country. For example, Fomes applana- 

 tus Pers., found in the heartwood of a variety of trees, is not 

 known to be a parasite in this country. The writer has specimens 

 of this fungus from Peru, with the statement that it attacks the 

 roots of fruit trees and does considerable damage. This would 

 lead one to think that it would be unsafe to introduce this par- 

 ticular strain (if it may be so called) or this species into this 

 country. 



Not until investigations in forest pathology in tropical lands 

 have reached as high a plane as they have in temperate zones will 

 we know what we may fall heir to from foreign countries. With 

 the increase in commercial intercourse with foreign lands and the 

 increased demands for the timbers and other plant life they pro- 



10 Buller. Loc. cit. 8. 



11 Weir, Jas. R. Notes 011 the altitudinal range of forest fungi. Mvco- 

 r.OGTA, 10: p. 4-14. 1918. 



