46 British Ui^edine^ and Ustilao-inecE 



CHAPTER VII. 



HETERCECISM. 



History. — The fact that a certain number of Uredines 

 possess the faculty of passing a part of their lives upon 

 one plant, and the remainder of it upon another and a 

 totally different one, is so remarkable that until quite 

 recently there were persons who declined point-blank to 

 believe it. It is quite unnecessary now to undertake seriatim 

 to answer the theoretical objections which have been 

 raised against the fact that heteroecism does occur, for 

 the simple reason that these objections are only theoretical. 

 The process of simply placing the spores of the fungi in 

 question upon their various host-plants is so easy, that 

 any one wishing to appeal to Nature herself can do so 

 with very little trouble. 



The first Uredine in which this peculiarity of develop- 

 ment was observed was Puccinia graminis, the wheat 

 mildew. The mildew of wheat has, as a blight, probably 

 been known from remote antiquity. The Romans held a 

 festival on April 25 — the Robigalia, or Rubigalia — with 

 the object of protecting their fields from mildew. The 

 sacrifices offered on this occasion consisted of the entrails 

 of a dog and a sheep, accompanied with frankincense and 

 wine.* In Wickliffe's Bible, the suggestion is made that 



* Smith, " Smaller Dictionary of Greek and Roman Antiquities," 5th edit. 

 (1863), p. 322. 



