22 MICROSCOPIC FUNGI. 



Cu 



CHAPTER IL 



SPERM0G0NES. 



IN addition to their spore-bearing spots, lichens 

 have for some time been known to possess other 

 organs, termed spermogones, which are probably 

 concerned more or less in the reproductive pro- 

 cess. The first intimation of the existence of 

 similar bodies in the entophytal fungi originated 

 with M. Unger in 1833, but it was left to Dr. de 

 Bary and the Messrs. Tulasne, twenty years later, 

 to examine and determine satisfactorily the nature 

 and value of the spermogones of the Uredines. 

 It was at first believed that the smaller pustules — 

 which sometimes precede, and sometimes accom- 

 pany, the cluster-eups and some other allied fungi 

 — were distinct species developed simultaneously 

 therewith, or members of a new genus, which, 

 under the name of JEcidiolum exanthematum, found 

 a place in the mycologic system. 



Without staying to trace the stages through 

 which the elucidation of their true nature pro- 

 ceeded, it will suffice for our purpose to tell what 

 is now known of these secondary organs ; to 

 accomplish which we must stand greatly indebted 

 to the independent researches of Messrs. de Bary 

 and Tulasne. It has been demonstrated that both 

 these bodies, namely, the primary organs or cluster- 



