110 TWENTY-FIFTH REPORT ON THE STATE MUSEUM. 
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Synopsis oF New Yorxk Poccrnra. 
PUCCINIA Pers. 
Uredo spores subglobose, brand spores uniseptate, supported on a 
distinct peduncle—Hand-book of British Fungi. 
The minute plants included in this genus are known by the 
common names brand, mildew and, in one condition, rust. They 
grow upon the leaves and stems of living plants, and consist of 
obscure filaments imbedded in the tissue of the affected part and of 
dense tufts or clusters of spores which spring froin them. In many 
species a discolored spot, which is also sometimes distorted or swollen 
in appearance, marks the position of these spore clusters. They are 
at first covered by the epidermis of the leaf, but as they advance 
toward maturity they push this up in the form of little swellings or 
pustules. Soon the pressure becomes so great that the epidermis 
bursts, revealing the little, compact, cushion-like cluster of upright 
spores, nestling within its rnptured walls. These spore clusters or 
sori, as they are sometimes called, vary in size in different species 
and even in the same species, but they seldom exceed one line in 
diameter. In some species found on grasses, they frequently become 
confluent or greatly elongated in one direction and form long parallel 
lines between the veinlets of the leaf. In one species they ; are scat- 
tered about irregularly, in another, crowded together in orbicular 
groups or patches, and in a third they are both scattered and clus- 
tered. Sometimes they occur upon both surfaces of the leaves they 
inhabit, but most often on the lower surface only, and very rarely on 
the upper surface alone. 
The color of the spores, as seen in a mass, is some shade of brown 
or black, and at a little distance the affected stems and leaves appear 
to be blackened in spots as if scorched by fire, whence probably the 
application of the term “ brand” to these ‘plants. 
A transverse septnm or partition at or near the middle of each 
spore divides it into two parts or cells. In some species the spore is 
much constricted at this dividing line, causing it to appear as if a 
band were closely drawn around it. In each cell a small globule or 
nucleus is sometimes seen, but this is not a constant mark. The 
young spores are paler in color and often more narrow and pointed 
than those that are mature. The prevailing forms are elliptical, oblong 
and clavate. Generally, in those species with elliptical spores, the 
peduncle is short and hyaline, but in other cases it is various, being 
short or long, hyaline or colored, according to the species. 
Species of Puecinia may be found almost any time from May to 
October, but the greater number of species appear in late summer 
and in autumn. Sometimes they persist through the winter, and old 
stems and leaves may be found in early spring, infested by the 
Puccinia of the preceding year. 
