oq6 natural history bulletin. 



included under Puccinia poculiformis which the authors have 

 strong reasons for believing are assuredly a part of it The 

 uredospores found among the teleutospores of t 1 " gathering 

 upon Triticum repens are somewhat smaller than those taken 

 from wheat stems, and even the teleutospores seem a little 

 smaller. But cultures made bv Charles B. Plowright of 

 King's Lvnn, England, fully establish the identity of the ma- 

 terial. In the spring of 1884 material gathered in the same 

 locality as that secured two years later for the present distri- 

 bution was sent to Mr. Plowright. The record of his experi- 

 ment runs as follows: "Exp. 384. A seedling Barberry 

 plant infected on 21 May with germinating spores of Puccinia 

 graminis on Triticum repens sent by Mr. J. C. Arthur from 

 Geneva, U. S. A. — 30 May spermogonia appeared, 5 June 

 aecidia, 22 the accompanying leaves gathered. — King's Lynn, 

 22, 6, '84. Charles B. Plowright." Four leaves of barberry 

 with fully developed aecidia, together with the memorandum, 

 are now in the Arthur herbarium. There seems to be no 

 reason, in view of these facts, to doubt that the form on Trit- 

 icum repens is correctly referred to P. -poculiformis. 



In regard to the gatherings on Agrostis, both on A. vulgaris 

 and A. scabra, the chance for reasonable doubt is more pro- 

 nounced. Both uredo and teleutospores are much smaller 

 than in typical material, and the form of the teleutospores is 

 clearly at variance, being less slender and pointed. Only 

 partial experimental evidence is available in this case. Cultures 

 with the uredospores from the culms of Agrostis alba were 

 made by Wm. Stuart during Jul v. 1898, in the botanical lab- 

 oratory of Purdue University. The leaves of wheat plants 

 infected with the spores July 6 showed characteristic pustules 

 and spores on July 21. The uredospores from the original 

 material, as well as the accompanying teleutospores, agreed in 

 size and appearance with those in this distribution (plate VI, 

 figs. 30/2 and 30/), measuring 19-26 by 14-17,0. The result- 

 ing uredospores grown on the wheat leaves measured 22-33 

 by 20-22,0, which is a return to the typical size of the species. 

 This would indicate that the undersize of the spores on species 



