334 
THALLOPHYTES. 
formed in cushion-like masses of mycelium upon densely-crowded branches (basidia) 
directed outwards immediately beneath the epidermis. They contain red granules and 
are perceptible with the naked eye as narrow long red projections upon the leaves and 
stems of Grasses. These uredospores are dispersed after the rupture of the epidermis, 
and germinate after some hours upon the surface of the Grasses (Fig. 224, D) : in these 
they form new mycelia which, in 6 or 10 days, bear uredospores again. While 
the Fungus is multiplying in this manner for several generations on Grasses during 
the summer in its uredo-form, the production of a new form of spores begins in the 
older uredo-fruits ; the long two-celled teleutospores begin to be formed near the 
roundish uredospores (Fig. 223, ///, /). The formation of uredospores in the uredo- 
FlG. 224. — Puccinia Graminis. A germinating teleutospore t, the promycelium of which forms the sporidia sp; 
B a. promycelium (after Tulasne) ; C a piece of the epidermis of the lower surface of the leaf of Berberzs vu/£-aris W\th 
germinating sporidium sp ; i its germinating filament penetrating the epidermis ; D a germinating uredospore 14 hours after 
dissemination (after De Bary, I. c). 
fruits then entirely ceases, and teleutospores only are produced (Fig. 223, //), and with 
them the period of vegetation closes. The teleutospores persist on the grass-haulms 
through the winter, and do not germinate till the spring; they emit from their two cells 
short septate germinating filaments (Fig. 224, B), the promycelia, at the ends of 
which, on slender branches, the sporidia are produced. These sporidia develope a new 
mycelium only when they germinate on the surface of the leaves of the Barberry ; their 
mode of germination differs from that of the other forms of spores, their germinating 
filaments penetrating, as in the Peronosporeae, into and through the epidermis-cell (Fig. 
224, C, sp and i), and thus reaching the parenchyma. They there form a mycelium 
