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258 ON SOME RUSTS AND MILDEWS IN INDIA.
These were collected at the end of the winter 1889-90. " Jowari
is usually a hot- weather ("kharif") crop; but a cold-weather, or
" rabi," crop is grown in some parts. The specimens of the
fungus I obtained were from the Poena Farm on " Shalu," a coldweather
Jowari. The leaves were spotted irregularly on both
sides with oval reddish-brown spots, black in the centre. The
black central parts of the spots were teleutospore pustules, and
these, though really naked, were overlapped by the raised and rent
epidermis.
On examining some spores scraped from these pustules they
were found to
spores.
consist mainly of ruccinia spores with some uredo-
The uredospores are brown, oval bodies, with the place of
attachment to the stalk usually clearly marked. After lying
twenty-four hours in water they measured 34-30 x 22-20 /x. The
epispore is beset' with shallow warts, and pierced by 4 to 5 germpores
on the short equator of the spore. They did not germinate
(fig. la.)
The teleutospores are deep brown and usually rounded at both
ends (fig. Ih. c), though some are slightly narrowed towards the
apex. They are shghtly constricted at the septum, and a piece of
stalk remains adherent. They are therefore rather firmly adherent
to the host. The epispore is uniformly thick and quite smooth.
After lying
29-22 /x.
twenty-four hours in water they measured 50-41 x
Among the scraped-off uredo and teleutospores are numerous
large capitate or club-shaped paraphyses ; some of these are
colourless, whilst others are deep brown (fig. 1, d.).
Aftar lying in water three days (24 x 3 hours) many germinated
in the usual way, the promycelia being colourless. The
sporidia are abstricted from long sterigmata ; they are colourless
and oval, measuring 15 x 10 /x (figs. 2, 8).
Remarks.—This affection, known locally as " Kani," is possibly
P. Su)yhi Schweinitz, and I have named it so provisionally, but it
is quite possibly a new species. I am the more inclined to think
it is a new species, because I have never seen nor received
specimens on Zea Mays in India ; and as the latter is very extensively
cultivated, this is unexpected on the assumption that the
fungus is P. Sorf/hi. Stih, as I have not had good opportunities
for obtaining information about the existence of any Rust on
Zea, it is quite possible that it exists. Assuming the fungus on
Sorghum to be P. Sorijhwn, the Indian species differs especially in
having considerably larger uredo and teleutospores ; in the teleutospores
not being thickened at the free ends ; and in the spores
being associated with paraphyses. The differences in the spore
measurements are best shown tabularly