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20 fournal of Mycology [Vol. 12 



plum) and from Anemone ranunculoides on P. spinosa, produc- 

 ing in each the characteristic uredospores of Puccinia Pruni- 

 spinosae, the rust of plums and peaches. 



This work by Dr. Tranzschel suggested the following trials 

 with American material. Aecidiospores from Hepatica acutiloba 

 (Aecidium hepticatum Schw.) were sown on three small plants 

 of Primus serotina (wild black cherry), established in pots in the 

 greenhouse, on Prunus Americana (native plum), P. Cerasus 

 (cultivated cherry), and Amygdalus Persica (peach), the last 

 two seedlings. The sowings were made May I to 4, and in fifteen 

 days afterward, uredospores appeared on P. serotina, but the 

 other plants remained wholly free, watch being continued for a 

 month and more. The successful sowings were as follows : 



May 1, Aecidiospores sown on P. serotina; May 16, uredospores; May 22, 



teleutospores. 

 May 1, Aecidiospores sown on P. serotina; May 16, uredospores. 

 May 2, Aecidiospores sown on P. serotina; May 17, uredospores. 



On May 23, a sowing of uredospores, which had been grown 

 on P. serotina, was made on A. Persica, under seemingly most 

 favorable conditions, but no infection took place, watch being 

 kept for two months. 



From these results there can be no further question of the 

 general identity of the American and European plum and cherry 

 rusts, and their connection with the Aecidium punctatum. It is 

 not possible to state what significance is to be attached to the 

 failure to infect peach, plum and cultivated cherry with spores 

 that readily infected the wild cherry. Careful search for two 

 seasons in the vicinity of the diseased hepaticas, the fungus being 

 perennial, has failed to detect any rust on plums, cherries or 

 peaches, wild or cultivated, although growing in plenty; and 

 furthermore Puccinia Pruni-spinosae has not yet been reported 

 from Indiana, although said to occur in the adjoining state of 

 Illinois on P. serotina, P. Virginiana, and P. Americana. 



20. Puccinia Xanthii Schw. Teleutosporic material 

 on Xanthium Canadense, gathered near Lafayette, Ind., on Nov. 

 5, 1904, was sown on the second and third leaves of seedlings of 

 the same species of host April 3. On April 8 small yellow dots 

 began to show, which closely simulated spermogonia, but which 

 microscopic examination by means of sections proved were only 

 the very young teleutosporic sori. The yellow dots increased in 

 size, appearing like small pimples, and finally broke through the 

 epidermis, exposing the teleutospores April 21, eighteen days 

 after inoculation. Another sowing was made April 13, on the 

 cotyledons of the same species of host, and on the second leaves 

 of Ambrosia trifida. The Xanthium seed-leaves showed yellow 

 dots on April 22, and open sori May 1, also in eighteen days 

 from sowing, but the Ambrosia leaves remained free. 



