323 



like a short cycle telial form comparable to Endophyllum, since the so- 

 called aeciospores germinate like teliospores. In a later study (Bull. 

 Torrey Club 43:559-569. 1916) Kunkel concludes that there are two 

 forms of orange rust of Rubus in North America. He found that in 

 certain collections the spores germinate as aeciospores with germ tube, 

 while in others they germinate as teliospores. Arthur (1. c.) concurs 

 in this view and establishes the genus Kunkelia for the short cycled 

 form. Atkinson (Am. Jour. Bot. 5:79-83. 1918) presents evidence in sup- 

 port of the contention that only one species should be recognized and 

 that it represents a form whose life history is unstable and that the 

 spores may germinate either as aeciospores which on infection develop 

 teliospores of Puccinia Peckiana, or as teliospores which, following in- 

 fection, result in a repetition of the caeomoid aecial form. He considers 

 that the behavior of the spores is dependent on certain conditions, the 

 most important of which is temperature. Until more evidence is avail- 

 able it seems best to continue to list this species under the old name. 



20. Gymnosporangium Botryapites (Schw.) Kern, Bull. Torrey Club 

 35:506. 1908. 



Caeoma Botryapites Schw. Trans. Am. Phil. Soc. II. 4:294. 1832. 



Gymnosporayigium biseptatum Ellis, Bull. Torrey Club 5:46. 1874. 

 On Juniperaceae : III. 



Chamaecyparis thyoides (L.) B.S.P., Seaford, April 14, 1908. 



Dr. W. G. Farlow (Anniv. Mem. Bost. Soc. Nat. Hist. 35:1880) was 

 the first to attempt infection experiments with this species. He reports 

 success in obtaining pycnia on Crataegus tomentosa. It is noteworthy 

 that later studies have not confirmed the occurrence of the species on 

 Crataegus. Later (Proc. Am. Acad. Nat. Sci. 12:313. 1885) spermo- 

 gonia were obtained on leaves and stems of Amelanchier canadensis. 

 Dr. R. Thaxter (Proc. Am. Acad. Nat. Sci. 14:263. 1887) obtained the 

 development of aecia on Amelanchier canadensis which were recognized 

 to be Roestelia Botryapites (Schw.) C. & E. These results were later 

 repeatedly confirmed (Conn. Agr. Exp. Sta. Bull. 107:4. 1891). 



Dr. J. C. Arthur (Mycol. 1:240. 1909) records successful infection 

 of Amelanchier intermedia from telial material collected by the writer 

 at Newfield, N. .J., pycnia only resulting. 



Dodge (Torreya 15:133-134. 1915; Bull. Torrey Club 42:519-542. 



