DISEASES OF THE SKIN, W 



the calyx of that fruit. These are esteemed 

 in the Levant for their aromatic and acid 

 flavour, especially vvhen prepared with sugar. 

 It may be remarked that all the excres- 

 cences above mentioned are generally more 

 acid than the rest of the plant that boars 

 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 under- 

 stood than the foregoing. Besides one kind 

 of Honey-dew, already mentioned p. 189, 

 something like leprosy may be observed in 

 Tragopogon major, J acq. Austr. t. 29, which, 

 as I have been informed by an accurate ob- 

 server, 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 dif- 

 ficult, in many cases, to judge whether such 

 appearances proceed from a primary disease 

 in the plant, arising from unseasonable cold 



