Arthur: Cultures of Urkdinkai. 23 H ^ 



as in the similar culture work of 1912, discussed above under 

 number 1. 



15. Puccinia vulpinoidis D. & H. A collection of this rust 

 on Carcx vulpinoidea (host determined by Dr. Theo. Holm) made 

 by Mr. Overholts at Elkton, Ohio, was used to sow April 17 on 

 Aster panic ulat us. A, Drummondii, Solidago canadensis, S. gla- 

 berrima (S. missouricnsis of most manuals), S. Rugosa, and S. 

 mollis. There was no infection of Asters, but a most abundant 

 infection of the four species of Solidago, pycnia showing in each 

 case April 27, and aecia May- 7. 



Puccinia zulpinoidis has been considered a distinctive and easily 

 recognized species on account of the covered telial sori. A care- 

 ful morphological study, chiefly by Dr. F. D. Kern, had shown 

 however, that aside from this character the spore structure and 

 range of hosts agree with P. Caricis-Solidaginis, or as we now say, 

 P. cxtcnsicola, and to this morphological study was due the sug- 

 gestion which led to the above successful cultures. The per- 

 manently covered telial sorus must be considered in the light of 

 this study to be associated with the structural peculiarities of the 

 host, and not a character to be used without qualification. 



16. Gymnosporangium clavariaeforme (Jacq.) DC. Mate- 

 rial on Junipems sibirica, sent by Mr. Bethel from Tolland, Colo., 

 was sown May 21 on Crataegus cerronus and gave rise to abun- 

 dant pycnia June 1, but no aecia matured. 34 



17. Periderm ium fusiform e Arth. & Kern. Through the 

 kindness of Dr. F. A. Wolf of Auburn, Ala., typical material 

 of this striking rust was received, gathered from a grove of 

 Pin us taeda, which Dr. Kern and myself had visited in April, 

 19 1 2, and in which this form of Peridertnium is very abundant. 



The first collection, sent March 22, 1913, was from a main stem 

 an inch in diameter, the fusiform gall being one and a half inches 

 in diameter at the middle, and six inches long. It was sown 

 March 24 on two plants of Quercns rubra. Uredinia began to 

 appear sparingly on one plant by April 3, but failed to appear on 

 the other, although telia developed on both plants April 14, in 

 ample and perfect development. 



3* For previous cultures see Jour. Myc. 14: 19. 1908; Mycol. 1: 239. 

 1909; 4: 24. 1912; and 4: 56. 1912. 



