VIII] 



UREDINALES 



209 



form ; in both cases it is borne in association with spermogonia on a 

 myceHum of uninucleate cells. But the spore germinates like a teleutospore 



Fig. 186. Endofhyllum Setnpervivi'L&v.; spores giving rise to 

 basidia ; both after Hoffmann. 



(fig. 186); its two nuclei fuse (fig. 187), its contents are extruded as a pro- 

 mycelium, two successive nuclear divisions occur, cross walls appear and four 

 basidiospores are produced, which, in due course, give rise to a uninucleate 

 mycelium. The sporophytic stage thus endures only from the fusion of the 

 fertile cells until the germination of the spores which they produce. 



Incidentally these observations in the case of Kunkelia nitens have 

 demonstrated that the caeoma of this fungus is not a stage in the life-history 

 of the teleutospore-producing Puccinia Peckiana on the same host, for the 

 mycelial cells ol P. Peckiana are binucleate and the teleutospores germinate 

 in the usual way. 



The development of an apo- 

 gamous aecidium has been ob- 

 served by Moreau in a variety 

 of Endophyllwn Euphorbiae on 

 Euphorbia sylvatica ; here the 

 basal cells, aecidiospores and 

 cells of the pseudoperidium are 

 uninucleate throughout their 

 development, the aecidiospore 

 germinates to form a promy- 



celium of three or four cells ^''f }^1: Endophyllum Sempervivil^v.; a. nuclear 

 i,i,iiLi..» ^. i.iiiv,^, ^L ^ fusion m spore; b. synapsis m fusion nucleus; after 



and neither nuclear association Hoffmann. 



G.-V. 



14 



