Jan., 1904,] Infection Experiments with Species of Rusts. 57 



ADDITIONAL INFECTION EXPERIMENTS WITH 

 SPECIES OF RUSTS. 



W. A. KEr<Lp;RMAN. 

 {Abstract.) 



General report of artificial cultures of Rust stages, both liete- 

 roecious and autcecious species, continuation of work reported 

 the previous year. Over twenty species were used and inocula- 

 tions of a very large number of host-plants were attempted. The 

 experiments numbered nearly two hundred. In nine cases posi- 

 tive results were obtained — some being repetitions of previous 

 successful experiments, others showing connections not previously 

 known. 



Of the latter it was shown that the Black Rust ( Puccinia 

 muhlenbergiae Arth.) on the common Muhlenberg Grass (j\Iuh- 

 lenbergia mexicanaj was the alternate stage of the Yellow 

 Cluster-cup fungus (Aecidium hibisciatum Schw.) on the Marsh 

 Mallow (Hibiscus moscheutos). 



Cultures with the Black Rust (Puccinia cirsii-lanceolatiSchroet.) 

 of the Common Thistle (Carduus lanceolatus L,.) resulted in the 

 development of aecidia or Yellow Cluster-cup stage (as well as 

 the red and black spores) but this has not before been reported in 

 this countr3\ The Rust has heretofore been called Piccinia cirsii 

 Lasch, but the experiment showed it to be P. cirsii-lanceolati, a 

 species described in Europe several years ago by Schroeter. 



In a similar manner it was proven that the Western Sage Rust 

 rPuccinia caulicola Tr. & Gall, on Salvia lanceolata) — material 

 for cultures received from Kansas in the earl}' spring (sent b}- 

 Mr. E. Bartholomew) — has a hitherto unrecorded aecidial stage 

 on the same host plant. 



Cultures demonstrated experimentalh' for the first time the aut- 

 eu-puccinial character of the Rust of Ruellia. That is to say, all 

 of the four stages grow on one and the same host. 



The paper is published in full in the December number of the 

 Joidiial of Mycology. A summar}' of the successful cultures may 

 be briefly stated thus, it being understood that the teleuto-spores 

 (black or winter spores) were used when sowings were made on 

 the host plants, and, in case of Puccinia lateripes, aecidiospores, 

 also : 

 Puccinia angustata (on Scirpus atrovirens) — aecidia on I^ycopus 



americanus. 

 Puccinia caulicola (on Salvia lanceolata) — aecidia on Salvia lance- 

 olata. 

 Puccinia caricis-erigerontis (on Carex festucacea) — aecidia on 

 Leptilon canadensis. 



