DISEASES OF THE QUINCE. 



and opening out with a multitude of cups, notched at 

 the edge, and shedding a profusion of yellow dust, which, 

 as it falls, reminds one of the shower of sparks from an 

 ascending rocket. The cups are bell-shaped, edged with 

 a pretty fringe around their margins ; and are so nu- 

 merous as to entirely girdle the twig or half cover the 

 fruit. 



These cups, called peridia by mycologists, appear to 

 have burst through the outer covering of the bark on 



Fig. 57. STEM BETWEEN BUDS AFFECTED BY THE K^ESTILIA AURANTIACA. 



the twigs and the skin of the fruit. The cups some- 

 times rise a tenth of an inch above the surface, with the 

 lower parts attached to the substratum. The bursting' 

 peridia shed a liberal shower of their golden dust around 

 them, whicli is scattered by the winds, carrying the spores, 

 or, more strictly, the protospores, because they produce 

 the true spores or fruit, so that each grain of this dust is 

 the seed of more of these epiphytal plants. Before the 

 oidium or fungus bursts out in the clusters of cups so 

 prolific of dust, the surfaces of affected parts show numer- 



