156 



EOT ANT. 



spores, and of the latter there are in most cases two or three 

 different kinds, which are produced earlier than those that 

 result from a fertilization.. 



324. The sexual organs and the spore-fruit resulting from 

 the act of fertilization bear a striking resemblance to those 

 of Coleochsete, the difference being such as may be ac- 

 counted for by taking into consideration the aquatic habits 

 a 



Fia. 78. Fis. 79. 



OS, apiece of a vesetative hypha, m, m, 

 Upon a fragment of tte epidermis of the leaf of the grape, and to wliioh it is fas- 

 tened by the suckers, A; o, hypha, with the suckers, h, seen in side view. Mag 



Pig. 78.- Grape-blight (Erysiphe). 

 ': of thf 



nifled 370 times. 



Fia. 79.— Grrass-blight (Erysiphe communis), a, vegetative filaments, with a 

 few suckers; 6, branches bearing conidia; c, separated conidia. Magnified 135 

 times. 



of the one and the aerial and parasitic or saprophytic habits 

 of the other. 



325. In the Blights, which are all parasitic, the jointed 

 filaments closely cover the leaves and other tender parts of 

 their hosts, and draw nourishment from them by means of 

 suckers, which project as irregular outgrowths from the 

 side next to the epidermis (Pig. 78). These suckers apply 

 themselves closely to the epidermal cells, and, in some 

 cases, appear to penetrate them. 



