8 BULLETIN 247, U. S. DEPARTMENT OF AGRICULTURE. 



For a number of years Prof. E. Bethel has collected from the leaves 



of Ribes longiflorum at Denver, Boulder, and elsewhere in Colorado 



a species of Cronartium which is apparently not identical with the 



European Cronartium ribicola. The senior writer collected abundant 



specimens of the uredinial and telial forms of this rust both at Boulder 



and Denver, Colo., in October, 1914. The telia of this Cronartium 



are larger, more abundant, and much more conspicuous than those 



of the European species. Although the fungus has been epidemic 



for several years on the Chautauqua grounds near Boulder, two young 



white pines (Pinus strobus) on the grounds not far from the diseased 



Ribes were free from the disease. This species apparently is able to 



whiter over on Ribes plants in the uredinial form. It may yet be 



found that the secial form is a Peridermium on one of our native 



pines. 



DISTRIBUTION OF THE FUNGUS. 



DISTRIBUTION OF THE ^CIAL FORM. 1 



The ascial form of the fungus, Peridermium jryriforme, is widely 

 distributed in the United States, having been found in 10 States: 



Fig. 1.— Outline sketch map of the United States, showing the known distribution of Cronartium -p-.iri- 

 forme. Localities where collections of the dilTerent forms of the fungus have been made are indicated as 

 follows: v, iEcial form on species of pines; a ( uredinial and telial forms on species of Comandra; X, all 

 forms. 



Arizona, California, Colorado, Montana, New Jersey, Pennsylvania, 

 South Dakota, Washington, Wisconsin, and Wyoming (fig. 1); and 

 when a more careful search is made for the fungus, in the light of our 

 present knowledge, it will no doubt be found to have a much more 

 general distribution in this country. It has also been found in 

 Alberta and British Columbia. 



1 All specimens cited except those marked wit h a star (*) have been examined by one of the writers. 



