194 



HEMIBASIDIOMYCETES 



[ch. 



pairs of associated nuclei takes place. Rawitscher observed a quite similar 

 life-history in T. lacvis. 



In the parasitic mycelium of Doassansia Alismatis and Entyloma Glaucii 

 (fig. 162) Dangeard observed binucleate cells and the fusion of their nuclei 



Fig ifi:. Development of brand-spores ; a. Doassansia Alismalis 

 1 \rcs) Corn.; l>. Entyloma Glatuii Dang.; after Dangeard. 



in pairs in preparation for the formation of the brand-spores. The same 

 stageswere recorded by Lutman mDoassansiadeformans,EntylotnaNynipheae 

 and Urocystis Anemones (fig. 163). 



Fig. 163. Urocystis Anemones (Pers.) Wint.; mycelium and young spore 

 ball ; afiei Lutman. 



Tuburcinia primulicola infects various species of Primula and gives rise 

 to conidia as well as to brand-spores during its parasitic stage. Wilson 

 has shown that the conidia develop in the young flower on a mycelium 

 of uninucleate cells which apparently persists in the host plant throughout 

 the winter. When the flower opens the conidia conjugate in pairs, and a 

 nucleus passes through the connecting tube so that one conidium is empty 

 and the other binucleate. Germ-tubes with paired nuclei are later produced 

 and doubtless give rise to the mycelium of binucleate cells which bears the 

 brand-spores. This mycelium ramifies in the superficial tissue of the placenta 

 and between the ovules, giving rise to brand-spores in the same flowers in 

 which the conidia were previously developed. On the germination of the 



