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ON SOME BUSTS AND MILDEWS IN INDIA. 259
Scliroter describes the uredospores as having three to four germporos,
and notes that the apex of the teleutospore is thiclcened to
5-6 [M. Saccardo states that the teleutospore pustules are without
paraphyses, whilst the absence of any reference to them throughout
Schroter's description leads to the conclusion that the European
species is entirely without them. The fungus has a very wide
distribution. Thus, iii Saccardo's ' Sylloge ' it is recorded in Italy,
France, Germany, North and South America, and South Africa.
Melampsora Lini Pers., on Linum usitatissimum L. ("Ulsee").
I obtained excellent specimens of a species of Melampsora,
gathered on the 4th April, 1890, at Dumraon, N. W. Provinces.
Tlie leaves were very extensively attackedwith orange-red pustules,
oval to round, but coalescing freely, and often involving most of the
leaf-surface. These pustules are mostly epiphyllous, and they are
often surrounded by a wall of epidermis giving them the appearance
of the fBcidial fructij&cation of Phragmidium. In other parts
dark crusts might be seen which were the teleutospore beds.
The uredospores are pale orange-red, and are accompanied by
colourless capitate paraphyses, sometimes of very large size, the
head exceeding the spores in diameter. They are round (fig. 4, a)
to oval, and the dried spores, when just immersed in water,
measured 21-18 x 18-16 /x. But after lying forty-eight hours in
water, most spores become spherical, measuring 24 to 21 jt*. in
diameter. The epispore is sparsely beset with spines. I could not
ascertain the number of germ-pores. The paraphyses had heads
measuring 30-28 x 20 //.
The teleutospores are long, cylindrical, or prismatic singlecelled
bodies, very firmly adherent to one another laterally
(fig. 4, h). They each exhibit a central nuclear space, and
measured, after lying forty-eight hours in water, 54-56 x 10-9 ia..
They did not germinate after lying some days in water even up to
June, and I conclude a period of rest is necessary before this can
take place.
Ilotiarks.— This is no doubt Melampsora Lini Pers. The spore
measurements of the Indian species are compared with the statements
of European authorities in the following table :