6 



BULLETIX ^5*7, U. S. DEPARTMENT OF AGRICULTURE. 



To sum up briefly: Pinus cembra, the probable original pine host, 

 ranges across northern Asia; and the fungus is reported from western 

 eastern, and central Asia, in some places where it may easily be 

 endemic. 



In North America, Cronartium rihicola was first found in 1906 at 

 Geneva, N. Y. (3, 150). Later findings have indicated that it was 

 here in the Northeastern States as early as 1898 (108, 136, p. 6). It 

 might have been in North America a few years, but not many, before 

 that date. This is supported by Clinton (13), who unsuccessfully ex- 

 amined specimens of Ribes wliich are in some of the larger herbaria 

 of the eastern part of this country. The writer has supplemented 



Fig. 3.— Outline map of the northeastern part of the United States, showing (by black dots) the known 

 distribution of white-pine bUster rust in North America to and including 1909. 



Clinton's work by examining the Ribes specimens in several addi- 

 tional herbaria. These include the Pringle herbarium at the Uni- 

 versity of Vermont and the local collections of the University of 

 Vermont; of Dartmouth College; of President Ezra Brainerd, of 

 Middlebury College; of Mr. C. A. Weatherby, of East Hartford, 

 Conn.; and of Mr. C. H. Bissell, of Southington, Conn. The most 

 notable herbarium examined was that of the Boston Society of 

 Natural History, which contains many New England collections 

 made in the early years of the nineteenth century. Moreover, such 

 keen fungus collectors as Farlow, Seymour, G. P. Clinton, Peck, 

 Ellis, George Clinton, Stewart, and many others, never collected 

 Cronartium rihicola until 1906, showing that it is a recent immi- 

 grant. Since 1909, when it was first found in North America on 

 white pines, Cronartium rihicola has spread until it is firmly estab- 



