UREDINALES 595 



elatina (M. Caryophyllacearum) , the witches' broom of the white fir 

 (sporophyte principally on Stellaria and Cerastium). 



Among the autoecious species of Pucciniaceae are Uromyces Betae, 

 the beet rust, U. appendiculatus (£/. Phaseoli), the bean rust, Hemileia 

 vastatrix, the coffee rust, and Phragmidium disciflorum and its relatives, 

 the rosaceous rusts; among the heteroecious forms are Puccinia, Pruni- 

 spinosae, the plum rust (gametophyte on Ranunculaceae), Puccinia 

 graminis, the highly specialized black rust of cereals and other grasses 

 (gametophyte on Berberis vulgaris and its relatives), P. dispersa, the brown 

 rust of rye (gametophyte on Borraginaceae), P. triticina, the brown rust 

 of wheat (gametophyte on Thalictrum), P. glumarum, the yellow rust of 

 cereals (gametophyte unknown), P. Lolu (P.) coronifera, the crown rust 

 of oats (gametophyte on Rhamnus) and Gymnosporangium Sabinae, G. 

 globosum and G. Blasdaleanum, the rust of apples and pears (sporophyte 

 on Juniperus or Libocedrus). 



