I: 



TELEUTOSPORES 



i- much thicker a1 the apex than olsou here ( Fig. |:J). While 

 tin' spores are standing in a densely crowded 

 sinus, the apex is the part most exposed to tin 

 \\eatlnT.aml tlicivti)!'.- mosl needing protection. 

 There is a thin endospore t" each cell: the 

 contents aiv granular and at first oily : there is 

 a largo and conspicuous nucleus in the centre 

 of each. This nucleus, in its resting stage, is 

 almost homogeneous except for its nucleolus, 

 and was mistaken by the older observers for 

 a " vacuole" 



Since the mycelium from which the teleuto- 

 spores, as well as the uredospores, were formed 

 contains paired nuclei, the cells of the teleuto- 

 spore were at first in the same condition. When 

 its wall, however, begins to thicken, i.e. when it is becoming 

 mature, the conjugate nuclei unite, and form one large fusion- 

 nucleus (Fig. 14). The two fusing nuclei, after the v< i\ 



Fig. 13. Teleuto- 

 spore of /'. 

 Caricis. x 600. 



Fig. 14. Formation of teleutospores of P. Falcariae (after Dittschlag) ; 

 a, the spore-bearing hypha; b, the same divided into pedicel and 

 spore-cell; c, the spore divided into two cells; d, a young teleuto- 

 spore ; e, the same after the fusion of the nuclei, x about 800. 



numerous conjugate divisions during the long period of growth 

 from the formation of the fusion-cell of the secidium, would be 

 related, as it were, like very distant cousins, especially since 

 the nuclear divisions during this period, though indirect, appear 

 to show a very simplified form of mitosis, tending rather to be 

 of the nature of amitosis. The fusion, as already intimated, is 

 not to be considered as the act of fertilisation, but merely as a 

 necessary preliminary to chromatin-recluction. 



