96 British Uredinee and Ustilaginee. 
cellular, and pervades all parts of the affected plant 
especially the cortical parts of the stem, and also to sor 
extent the pith. It also occurs in the upper part of tk 
root-stock. It is hyaline, about 4°5u wide, richly branche: 
and septate. Its contents are colourless and vacuolate: 
The spores are formed inside the mycelial hyphe, whe: 
it becomes coarsely granular, much after the manner « 
Entyloma.* Woronint finds that the mycelium is abu 
dantly provided with very marked haustoria, which ente 
the cells. These botryform prolongations enter and occup 
a third or a half of their interior. Germination takes plac 
in autumn. Specimens gathered in June germinated i 
October and November. The epispore splits, and th 
endospore grows out as a blunt cylindrical promyceliun 
At its extremity it emits a cluster of from four to seve 
apical branches. The outgrowth of the endospore is < 
first often in the form of two equal branches, one 
which develops into the promycelium, while the othe 
ceases to grow and has become emptied of its protoplasn 
which passes into the developed branch. Towards th 
upper half of the promycelium a septum appears, cuttin 
off the protoplasm above from the empty tube below; bt 
true spore-formation was not observed. 
Tubercinia—The germination of the spores of 7. trée 
talzs has been worked out by Woronin.t Teleutospore 
collected at the end of September and the beginning 
October were found often to have already germinated upo 
the plant. Placed in a damp atmosphere, they germinate 
freely after the manner of Tilletia, each spore producing 
promycelium surmounted by a cluster of spores. All th 
teleutospores of one spore-ball do not germinate at th 
* De Bary, loc. czz. 
t Woronin, /oc. cit., pp. 27, 28, t. iv. figs. 27-35. 
$ Woronin, ‘‘ De Bary und Woronin Beitrage,” 5 reihe (1882), pp. 4-1 
t. i, ii, iii, figs, I-12. 
