4 SOME DISEASES OF CEREALS. 
less developed, those seen being chiefly simple finger-like processes 
entering the parenchymatous cells. 
Excepting for the absence of a sporangial stage, the fungus 
agrees with that on Pennisetum. ‘The oogonia are similar in shape 
and colour and measure 38 to 50# (average 41+), thus being 
slightly smaller than on the first host. The oospores are 27 
to 33u (average 324 ), thus agreeing with the other. I can find 
no constant difference sufficient to refer the fungus on the two 
hosts to different species. 
The third cereal disease caused by a Sclerospora in India is 
very briefly referred to by Mr. Barber in the same paper as the 
above. It occurs on Setaria italica in Madras, being very abundant 
in some parts. I have only examined specimens kindly provided 
by Mr. Barber, and have not seen it in the field. These showed 
the same distortion and shredding of the leaves as in the pre- 
vious cases (plate IV, fig. 3). The latter were crowded with 
oospores, agreeing with those on the other hosts in shape and 
colour, and 36 to 46“#(average of twenty measurements 41*5p ) 
and 26 to 34# (average of twenty measurements 30+ ) respectively, 
in diameter. Hence, though the asexual stage was not observed, 
the fungus cannot be separated from those on the other hosts. 
The last of the Indian Sclerospora diseases which I have seen 
was found on Euchlena (Rheana) luxurians on. the Poona Govern- 
ment Farm, in 1905. The sporangial stage alone was observed, 
and agreed perfectly with that on Pennisetum which was common 
in the vicinity. Only early stages of the disease were seen, and 
hence oospores could not be discovered. The host plant was being 
experimentally grown on the farm and is not, so far as I am aware, 
cultivated anywhere in India, though an important fodder in some 
parts of the world. The disease is therefore of minor importance 
in this country. 
The whole of the characters of these fungi correspond to the 
type of the genus Sclerospora. Of this three species have been re- 
cognized in the most recent work on the genus, and a fourth should 
probably be added, to include Peronospora Maydis Raciborski 
(1897). Thus extended, it embraces all the Peronosporacee which 
