Dodge and Adams: Gymnosporangia on Myrica 27 



per cent. ; G. clavariaeforme invariably gave 95-100 per cent, 

 germination if the watch glasses were left uncovered in the damp 

 chamber. 



The salmon color of the spores of Aecidium myricatum is due, 

 as in many other spore forms, to the color of the spore contents. 



Fig. 1. a. Aecidiospore of Gymnosporangium myricatum twenty-two hours 

 after the beginning of the germination test experiment. Three germ pores ap- 

 pear in one plane. Most of the orange-colored contents have moved out into 

 the germ tube. X 450. b. A germinating teleutospore of Gymnosporangium 

 myricatum. X 450. 



The germ tube emerges from the germ pore and immediately en- 

 larges considerably (Text-fig. 1, a) ; it sometimes branches rather 

 irregularly. The wall of the spore is only slightly thickened 

 about the germ pores. The brown color of the spores of the 

 other species of Gymnosporangium mentioned above is in the 

 spore wall, and there is, for example, in G. clavariaeforme a very 

 prominent thickening of the wall about the spores. Sorauer's 

 figure 50 9 (1906) of a germinating aecidiospore does not ade- 

 quately bring out these features. 



Reed and Crabill (1915) obtained much higher percentages of 



