TAB. CCCCXI.
UREDO Porri.
This pretty parasite was found on the waste part of the leaf of a leek, toward the base, and was most conspicuous within the leaf. It is not uncommon, and I believe does not much hurt the growing plant. It seems to burst from under the cuticle like other Uredos, and is composed of a number of round, nearly transparent, light green stiped capsules, each about 1OOOdth of an inch in diameter, containing apparently bright orange seeds.
It is somewhat remarkable that this kind of parasite grows on living plants, whereas the Sphaeriæ and many others are more usually found on decaying or dead vegetables. I presume a little marked attention will point out the way to avoid these evils, which, if such attention be omitted, may occasionally aggregate into a serious evil. We ought to thank Sir Joseph Banks for his account of the Blight in Corn, Uredo Frumenti, tab. 140.; and his highly magnified figures. It is a very laudable undertaking for men of fortune to support the more expensive elucidations in Natural History.
We have no doubt of seeds floating in the air, notwithstanding De Candolle's[1] argument. See Description and Tab. 136 and tab. 318. Hellvella membranacea, which is attached to living mosses and grasses by a thin film.
- ↑ De Candolle sur les champignons parasites. Annales du Museum d'Histoire Naturelle, tome neuvieme, 1807.