36 British Uredinece and Ustilagi^tecs. 



CHAPTEP. VI. 



TELEUTOSPORES. 



At some period in the life of all Uredines * a spore is 

 produced from one of the before-mentioned mycelial de- 

 velopments, to which the appellation teleutospore has been 

 given. In the strict sense of the term teleutospore means 

 the last-formed spore — that is to say, it is formed later in 

 point of time than the aecidiospores and uredospores ; but 

 while this is true in the majority of cases, yet there are many 

 species of the Uredineae in which no other spore-form than 

 the teleutospore occurs. Still, the name has become so 

 familiarized to us by long usage that it is unadvisable to 

 change it. These spores are formed in a similar manner 

 to the uredospores from a stroma (spore-bed, clinode, 

 hymenium) produced by an aggregation and entanglement 

 of mycelial hyphse placed just beneath the cuticular 

 structures of the host-plant and parallel to them. Per- 

 pendicularly from this stroma are given off erect branches, 

 which, becoming dilated at their free ends, are soon in- 



* De Bary (" Vergl.,'' p. 305) points out that Uredo syiiiphyti\\z.s no other 

 spore-form than the Uredo, and indicates this species as being a degenerate 

 type, which, having lost its other spore-forms, is capable of existing without 

 them. Without questioning the truth of this statement, one cannot fail to re- 

 member that until quite recently the other spore-forms of many Uredines were 

 unrecognized, for instance, Melampsora cerastii ; so it is quite possible that the 

 teleutospores of U. symphyti may exist, although we at present do not know 

 of them. 



