107 
THE PRINCIPLES OF BOTANY. 
By Professor James Buckman, F.G.S., F.L.S., &c. &c. 
(Continued from p. 33.) 
W e come now to an examination of a series of simply con- 
structed plants, to which the name Blights have been given. 
Bailey describes the word — (C Blight, a hurt done to corn or 
fruit trees, which makes them look as if they were blasted,” 
and it is derived from the German “ Blitz, lightning, sudden 
splendour, glance,” upon the supposition that the effects ob- 
served in vegetable (< blights” are due to some unexplained 
atmospheric causes. 
We now proceed to describe a few of these blights, with 
especial reference to those affecting some of our corn crops, 
as such a review can hardly fail to be useful to the student 
of the effects of vegetable upon animal life. 
Some of the simpler forms of blights are classed by the 
botanist under the genera of Uredo and Puccinia, and to 
these we would now direct particular attention. 
Uredo. — Sporidia free, aggregate, covered by the epider- 
mis of living plants, named from Uro, to burn. 
Puccinia. — Sporidia, one or more, supported by a filiform 
peduncle, named from Puccini, a Florentine professor. 
Both of these genera are so general that some species may 
almost be said to be peculiar to every plant, and therefore 
the second or specific name is usually derived from the 
higher plant upon which it is found, as thus, U. betas, U. 
primulas, P. menthae, P. primulas, &c. &c. ; and it becomes 
then a question of great importance whether the specific 
details are such as, in all cases, to entitle the forms to rank 
as perfectly distinct species, or whether they may not be 
varied by the constitutions of the different plants they affect. 
As regards the Uredo we, however, find that a single family 
will be effected by different forms — a fact which will at once 
be seen from the following enumeration of species of Uredo 
upon cereal crops. 
1. Uredo segetum. — The smut of wheat, barley, and other 
grass flowers. 
2. „ caries. — Bunt or smut of wheat seeds. 
3. „ rubigo. — Rust of the chaff scales of wheat. 
4. ,, linearis. — Rust of grass leaves. 
1. A ramble through almost any field of barley, when this 
