188 



Mycologia 



P. taeda, Florida, in 1915, Brookville, March 12 (17439); in 

 1916, March 17 (20782) ; in 1919, March 2 (32165), March 11 

 (32229). 



II and III. On Adelia: 



A. ligustrina, Florida, in 1918, Gainesville, May 6 (25298, type 

 of Coleosporium minutum) ; in 1919, May 14 (32363, 32862) ; 

 Brooksville (32395) ; District of Columbia, in 1918, Washington, 

 June 20 (29194). 



Coleosporium elephantopodis 



The successful inoculation of Elephantopus with P eridermium 

 carneum Am. Auct. was first reported in 1917 (8), indicating the 

 possible identity of Coleosporium elephantopodis (Schw.) Thiim. 

 with Coleosporium carneum (Bosc) Jackson (C. vernoniae B. & 

 C). A careful study of these two species, however, has estab- 

 lished the fact that they are not identical (10). The two are 

 distinct in their host adaptation, in addition to slight differences 

 in morphology. Even if these two species are not considered 

 separate and distinct, they must at least be considered races* of the 

 same species. The writers choose to treat them as separate 

 species, for reasons which follow : 



Of 22 sets of inoculations made with P eridermium carneum in 

 1914, 8 infected plants of species of both Elephantopus and 

 Vernonia, and 14 infected only those of Vernonia. Of 44 sets 

 of inoculations made in 191 5, 3 infected plants of species of both 

 genera, 4 only those of Elephantopus and 37 only' those of Ver- 

 nonia. Of 28 sets of inoculations in 1916, 8 infected plants of 

 species of both genera, 8 only those of Elephantopus, and 12 only 

 those of Vernonia. In 191 6 an effort, partially successful, was 

 made to separate collections of Peridermium carneum by macro- 

 scopic characters into two lots, the one belonging to Coleosporium 

 elephantopodis, the other to Coleosporium carneum. Later efforts 

 have been quite successful. 



From 1916 to 1919, 31 sets of inoculations have been made 

 from aecial material adjudged to be the aecia of Coleosporium 

 carneum; of these 24 infected only plants of species of Vernonia, 

 7 infected those bf both Vernonia and Elephantopus, and none of 



