Arthur : Amphispores 



37 



equator. The pedicels are long and persistent, and resemble those 

 of the teleutospores. The son" look like the teleutosori. They 

 sometimes have an intermixture of either uredospores or teleuto- 

 spores, but more often are without either. They are the most 

 abundant spore-form of the species. It is not yet known what are 

 the favorable conditions for germination, and Carleton * is yet 

 alone in a successful attempt to start them into growth. In a 

 study of the evolution of this form the fact, that occasionally the 

 usually smooth teleutospores show on their apical portion a ver- 



ir 



i 



I 



Figure i. Puccinia vexans Farl.; on Athei'ofogon curtipemhiiits. Central 

 United States and Mexico. II, Uresdopores, X, Amphispores. 



Figure 2. Puccinia Tripsaci D. & H.; on Tripsactim dactyloides. Soutliern 

 United States and Mexico. II» Uredospore. X, Amphispores. 



rucose sculpturing similar to that of the amphispores, will doubt- 

 less prove significant. The species ranges from Iowa and Nebraska 

 to central Mexico. 



2. Puccinia Tripsaci D. & H. {Uredo pallida D, & H.) has 

 remarkably small, very pale uredospores, with very thin, minutely 

 verrucose-echinulate wall, having four equatorial pores. The son 



appear w^hite. 



The amphispores resemble the uredospores in shape, echinula- 

 tion and germ pores, but are immensely larger in every way. 

 The wall is cinnamon-brown, and the sori are conspicuous. They 

 occur in connection with the uredosori, teleutosori, or alone. 



* Investigations of rusts. Bull. Bureau PI. Ind. 63 : 23. 1904 



