^34 



Journal of Mycology [Vol. 10 



water in the laboratory in lieu .of a potted plant, gave some 

 spermogonia, but the leaf fell from the stem before the time for 

 the appearance of the aecidia. It would have undoubtedly been 

 a successful infection, had the conditions been favorable for 

 maintaining the vigor of the host. This species is based upon 

 cultures made by the writer 7 in 1901. Its exact standing is yet 

 in some uncertainty, arid probably can" not be settled until the 

 connection of the very common aecidium, or aecidia if more than 

 one kind, on the several species of Ribes is ascertained. Dr. J. 

 J. Davis 8 has expressed the opinion that the whiteness of the 

 aecidial cups is probably due to the conditions under which they 

 are grown, and that they are normally orange-colored and iden- 

 tical with the common form. But the facts can only be ascer- 

 tained by cultural studies. 



5. Puccinla Heltanthi Schw. Ample teleutosporic ma- 

 terial was available in vigorous germinating condition, collected 

 by Prof .\Y. A. Kellerman at Sandusky. ( )hio, and by the writer at 

 Fair < >aks, End. All of it was on Helianthus mollis. Sowings 

 began on April 29, and continued at intervals until June 2, 

 twenty cultures being attempted. The sowings on H. stntmosus, 

 II. tuberosus, II. grosse-serratus, H. rigidus, and H. Maxi- 

 m ilia ui gave no infection. The sowing on H. tomentosus gave 

 a slight infection, a few spermogonia appearing but reaching no 

 further development, although the leaves were young and the 

 plants exceptionally vigorous. On H. mollis and H. annuus an 

 exceedingly strong infection was produced, numberless spermo- 

 gonia appearing, followed by well developed aecidia in great 

 quantity. The first sowings on H. mollis were made May 6, the 

 first spermogonia appearing May 16, and the first aecidia May 22 

 and 23. A second sowing was made May 29, giving spermogonia 

 June 7. and aecidia June 16. The sowing on H. a minus was 

 made June 2, showing spermogonia June 8, and aecidia June 17. 



Cultures of the Helianthus-rust were made during the pre- 

 vious year's work, 9 employing spores from H. grosse-scrratus, 

 which were found to grow upon the same host and the similar 

 //. Ma.vimiliaui, but not upon 77. strnmosus. Judging from the 

 work of the two years, it appears possible to divide the Heli- 

 anthus-rust into at least three series, for which the forms on H. 

 mollis, H. stntmosus and H. grosse-serratus may be taken as 

 representatives respectively. Dr. E. Jacky 10 of Switzerland has 

 made cultures, and has come to the conclusion that there are two 

 species of Helianthus-rust, for which the names P. Helianthi 

 Schw. and P. hclianthorum Schw. are to be used. It seems to 



7 Jour. Mycol. 8 :53. 1902. 



" Trans. Wis. Acad. Sci. 14 :88. 1903. 



8 Bot. Gaz. 55:17. 1903. 



10 Centr. f. Bakt. o 2 :841. 1902, 



