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 Rh the calyx of that fruit. These are esteemed in the Levant for their aromatic and acid flavour, especially when prepared with sugar.

It may be remarked that all the excrescences above mentioned are generally more acid than the rest of the plant that bears them, and also greatly inclined to turn red. The acid they contain is partly acetous, but more of the astringent kind.

The diseases of the skin, to which many vegetables are subject, are less easily understood than the foregoing. Besides one kind of Honey-dew, already mentioned p. 189, something like leprosy may be observed in Tragopogon major, Jacq. Austr. t. 29, which, as I have been informed by an accurate observer, does not injure the seed, nor infect the progeny. The stem of Shepherd's Purse, ''Engl. Bot. t.'' 1485, is occasionally swelled, and a white cream-like crust, afterwards powdery, ensues. The White Garden Rose, Rosa alba, produces, in like manner, an orange-coloured powder. It proves very difficult, in many cases, to judge whether such appearances proceed from a primary disease in the plant, arising from unseasonable cold