Arthur: Cultures of Uredineae in 191 i 63 



L., collected at Newfield, N. J., by Messrs. F. D. Kern and B. O. 

 Dodge, was sown May 4 on Aronia arhutifolia, Amelanchier can- 

 adensis, Pyrus communis, Mains coronaria, and M. Mains, with 

 infection on the first only, showing pycnia in abundance June 15, 

 but failing to develop aecia. 



Although this infection did not proceed to a sufficient develop- 

 ment to show the identity of the aecia, yet there are some reasons, 

 chiefly relating to host and geographical distribution for think- 

 ing that we are dealing with Roestelia transformans Ellis, which 

 was described by Mr. Ellis from material collected at Newfield, 

 N. J., on Aronia arhntifolia. 



6. Gymnosporangium gracilens (Peck) Kern & Bethel (G. 

 speciosum Peck), on Juniperus monosperma (Engelm.) Sarg., 

 sent by Mr. Bethel from Trinidad, Colo., was sown April 26 on 

 Crataegus foment osa, Sorhus aucuparia, and Philadelphus coro- 

 narius, with heavy infection on the last, showing pycnia May 6, 

 and aecia May 29. Before the infection had become certain 

 another sowing was made May i on Amelanchier vulgaris, and 

 the day following again on another plant of the same host, and 

 also on the fruit of A. erecta, as well as the leaves of Philadel- 

 phus coronarius. Again infection was secured only on the Phil- 

 adelphus, the pycnia showing in the greatest abundance May 13, 

 and aecia June 8. 



This connection was suggested by Mr. Bethel, who has given 

 a history of his observations in a recent number of Mycologia.^^ 

 The result of this set of cultures was communicated to Dr. F, D. 

 Kern, then residing in New York, which enabled him to complete 

 the description and synonymy of the species and to list the aecial 

 hosts in his monograph of the genus Gymnosporangium.^^ The 

 connection is especially notable, as it carries the aecial hosts of 

 Gymnosporangium outside the families of Malaceae and Rosaceae, 

 into the Hydrangiaceae. As the studies of this genus progress 

 more and more evidence is secured to show that it possesses out- 

 lying species approaching in form and habit some of those in 

 other genera. 



Bethel, Notes on some species of Gymnosporangium in Colorado, Mycol. 

 3 : 156-160. 191 1. 



See Bull. N. Y. Bot. Garden 7: 458. 1911. 



