BY D. McALPINE. 
147 
Investigations. 
I have examined a large number of specimens this season from 
different districts and have found the fungus, as already stated, 
on peach, nectarine, plum, apricot and almond. I have also 
specimens from the Herbarium of the United States Department 
of Agriculture, through the courtesy of B. T. Galloway, Chief of 
the Division of Vegetable Pathology, and these may be taken as 
a starting point. 
On the leaves of Prunus americana, the plum of North 
America (3rd Oct., 1889), there is nothing to be found but two- 
celled teleutospores, while on the leaves of another species of 
Prunus (28th Sept., 1889) there are a few uredospores, but the 
great majority are teleutospores. Fig. 1 shows (a) the uredospore 
which is yellowish-brown in colour, (b) paraphysis which is of a 
pale lemon-yellow colour, and (c) teleutospores which are of a 
dark brown, the lower equally so with the upper, but in many 
cases paler. There is no doubt but this fungus is Puccinia pruni, 
Pers. In the Victorian specimens the presence of two-celled 
teleutospores will settle the point that the fungus is not a 
Uromyces, and the teleutospores are common enough, so that it is 
a Puccinia. But if the peach leaf is examined in the summer 
season and even up to July in many cases, only one kind of spore 
will be found — the uredospore. And even on the plum leaf In 
the month of March I was unable to find a single teleutospore. 
On the peach leaves sent from Queensland by Mr. Tryon I 
found both uredospores and teleutospores (figs. 2 and 3). The 
uredospores were of the normal shape and varying in size from 28 
to 31 n long x 14 to 16 fx broad. The teleutospores were also 
normal, varying from 25 to 34 fx long x 17 to 20 jx broad, and the 
pedicels were short and transparent. By gentle pressure the two 
cells of the teleutospore can be readily separated, and in fact they 
often fall asunder in the process of mounting. The upper cell 
seems to be more brittle than the lower, as it is often broken up 
under slight pressure, while the other usually remains intact. I 
have drawn a lower cell (fig. 2c) separated by gentle pressure, 
