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numerous irregularities, which were incipient branches (fig. 5). Not unfrequently 
the end of the tube trifurcated in the manner of a trident (figs. 6 and 7). Usually 
one only of the main branches of the trident continued its growth, the others re- 
maining rudimentary. From this point all semblance of regularity in the contour 
of the tube was lost, and it gave off lateral branches, somewhat after the manner 
of a stag’s horn. The extremity of the tube did not even now lose its tendency to 
convolute, although this movement is considerably diminished (fig. 8). The yellow 
endochrome had by this time all accumulated in the irregular branched part of the 
tube, for although the lower portion above the septum was obviously not empty, 
yet the only distinctly yellow colouration was to be seen in the distal branched 
portion. 
Tt is obvious that the spiral movements above described are of great impor- 
tance to the fungus, as by them the growing mycelial tube has the chance of its 
catching on any irregularity of the cuticle of the best plant greatly increased. 
This catching power is enhanced too by the trident-like terminal extremity with 
its irregular branched outline. It is possible that the non-development of some of 
the terminal branches is not a purely accidental circumstance, but a provision by 
which the mycelium may become fixed upon the leaf, while the favoured branch is 
penetrating it. The ultimate changes which were observed in the mycelial tube 
were simply that it appeared to become septate. 
Similar results to the above were obtained from watching the germination of 
the Uredo of Coleosporium tussilaginis, Lev. ; of Phragmidiwm mucronatum, Link ; 
of Uromyces appendiculata, Lev. ; and of Acidium crassum, Pers. 
On the 12th and 13th August, 1881, some spores of Uredo linearis were 
observed to germinate in quite a different manner, for instead of producing the 
irregularly outlined branches (the stag’s horn branches), the terminal extremity of 
the tube became expanded in a globular manner, into which all the yellow endo- 
chrome accumulated (figs. 10—12). Often a secondary globular expansion took 
place at a lower part of the tube (figs. 11 and 12). Whether these bodies were 
really secondary spores, and, as such, fell away from the tube, or whether they 
were simply reservoirs into which the endochrome was accumulated previous to 
making a fresh departure in mycelial development, could not be clearly made out, 
but as they were not observed presenting any tendency towards the isolation of 
their contents by a basal septum, nor were any of them subsequently to be seen 
floating about, as they must have done had they fallen off, the presumption is in 
favour of their being endochrome reservoirs. Be this as it may, this method of 
germination presents a very much closer analogy to the true puccinoid germination 
than was observed in any other Uredine, excepting in Coleosporium,* in which 
genus it seems to be the normal method. 
The Acidia, as far as I have observed them, germinate in the same manner as 
other Uredines, although Tulasne has described and figured one species dc. 
* Tulasne, ‘‘ Ann. des Sciénces Nat.,” 4th Series, t. 8, f. 1, 8, 10, and zz. 
