396 



BOTANY 



PART II 



In the life-history of most Pyrenotuycetes tin- formation of perithecia is 

 preceded by the production of various accessory fructifications, particularly of 

 -conidia, which arc abstricted in dim-rent ways, cither directly from the hypha> 



- c 



Fir;. 339. Tuber nijinii. 1. A friictilicution in vertical section ( x 5) ; , the cortex : 

 d, air-containing tissue ; <. dark veins of compact liyplia- ; h, aseoxenous tissue : 

 3, a jiorticin ot'tlie hyineniiiin (x 460). (At't'-i TI T I.ASXK. IVmn v. TAVEL.) 



or from special conidiophores. and assist in disseminating the fungus. The 

 conidiopliores are frequently united in distinct, conidial fructifications. A 

 special form of such fructifications are the PVCNIIHA produced by many genera. 

 They are small spherical or Mask-shaped bodies which give rise to branched hyphal 

 filaments from the apices of which conidia, in this case termed PYCNOSPOIII.S or 

 , are abstrictcd Fig. :$:}7, 1. 2). The structure of the pycnidia and 



