10 British Uredinee and Ustilaginee. 
to the apex of the cone. The outer walls of this body are 
embedded between the cells of the host-plant, and are like- 
wise composed of similar fine hyphae, placed side by side. 
A section of the spermogonium at this time shows its 
interior to consist of similar converging parallel hyphz. 
Very soon those hyphz which constitute the emerging 
apex separate from one another, so as to appear as a brush 
of stiff hair like bodies (paraphyses) ; in the centre of this 
brush is a minute canal, which passes downward to the 
interior of the body of the spermogonium (Plate I. Fig. 4). 
The apices of those converging hyphze which occupy the 
lower part of the spermogonial interior, are now seen to 
be surmounted by very minute irregularly oval or rounded 
bodies (Plate I. Fig. 5)—the so-called spermatia. These 
spermatia vary in size, not only in the different species, but 
also in the same spermogonium. In those I have examined, 
they were from 5 to 8u long, and 3 or 4 or even 6u wide. 
Tulasne * gives the measurement of the spermatia of 
Triphragmium ulmarie and Puccinia fusca as from § to 
6u long, while those of most the A®cidia and of Coma 
pingue and C. ridesii are rarely more than 4u long. The 
spermatia are produced in linear series from the apices of 
the hyphz (sterigmata), which fill the interior of the sper- 
mogonium. These are held together by a viscid, gelatinous 
substance, which at first fills the bottom of the canal; but 
as more spermatia are produced, gradually the whole canal 
becomes full, and eventually the mass oozes out at its upper 
end in the form of a globule. The cause of the expulsion 
of the spermogonial mass is, as De Bary ¢ has shown, the 
imbibition of moisture, which causes the investing gela- 
tinous material to swell. As the spermogonium advances 
in maturity, its flask-like neck opens out, so that, instead 
* Tulasne, ‘‘2e Mémoire,” p. 118, 
+ De Bary, ‘‘ Brandpilze,” p. 60, 
