376 BROOKLYN BOTANIC GARDEN MEMOIRS 



1. Campanulae-rapunculoides Kleb. on Campanula rapunculoides and, 



in favorable cultures, on C. bononiensis, C. glomerata, C. 

 glomerata var. dahurica, C. lamiifolia, C. latifolia, C. nohilis, 

 Phyteuma orbicular e and Ph. spicatiim; not on Campanula 

 rotundifolia, nor C. trachelium. 



2. Campanulae-trachelii Kleb. on Campanula trachelium and, in favor- 



able cultures, on C. bononiensis, C. glomerata, C. glomerata var. 

 dahurica, C. latifolia var. macrantha, C. nobilis, C. rapunculoides 

 and Wahlenbergia hederacea; not on Campanula pusilla, C. 

 rotundifolia nor C. turbinata. 



3. Campanulae-rotundifoliae Kleb. on Campanula rotundifolia and, in 



favorable cultures, on C. bononiensis, C. glomerata var. dahurica, 

 C. pusilla, C. turbinata, Phyteuma orbiculare. Ph. spicatum and 

 Wahlenbergia hederacea; not on Campanula rapunculoides nor 

 C. trachelium. 

 Wagner indicated the following additional races: 



4. Campanulae-Phyteumatis Wagner on Phyteuma spicatum. 



5. Campanidae-macranthae Wagner on Campanula macrantha (C. 



latifolia var. macrantha). 



6. Campanulae-patulae Wagner on Campanula rotundifolia and C. 



pattda. 



Klebahn, however, does not believe that these can be distinguished 

 from the first three. It may also be noted that a number of plants 

 occur as hosts for more than one race. 



Coleosporium Senecionis Fr. Wagner (168) first gave evidence of 

 host specialization in this rust. Fischer (54) has also investigated the 

 rust and the following races are indicated: 



1. Senecionis silvatici on Senecio silvaticus, S. viscosus and S. vulgaris 



{Senecionis I of Wagner). 



2. Senecionis Fuchsii on Senecio Fuchsii and S. nemorensis {Senecionis 



1 1 of Wagner) . 



3. Senecionis subalpini on Senecio subalpinus {Coleosporium subalpinum 



Wagner) . 



4. Senecionis doronici on Senecio doronicum. 



Melampsora Euphorbiae (Schub.) Cast. This rust, completing its 

 life cycle on species of Euphorbia, has been studied by W. M tiller 

 (105, 106) who claims the existence of the following races: 



1. Euphorbiae-cyparissiae W. M tiller on Euphorbia cyparissias. 



2. Euphorbiae-exiguae W. M tiller on Euphorbia exigua. 



3. Euphorbiae-pepli W. Muller on Euphorbia peplus. 



Melampsora Euphorbiae dulcis Otth. This autoecious rust on 

 Euphorbia is very similar to Melampsora Euphorbiae. As a result of 

 the experimental work of W. Muller (105, 106) and Klebahn (91) two 

 races are indicated: 



