PERO&O3POIUE. 



259 



the sexual organs ; the asexual reproductive organs, on the 

 contrary, are on the surface of the host. 



343. The asexual reproduction takes place in the genus 



.&' 



w f 



Fig. 176. Cysiopus candidw. A, branch of mycelium, f, growing at the apex, , 

 and giving off haustoria, h, into the cells of the pith of Lepidium sativum. B, co- 

 nidia-bearing porti >m of the mycelium, with conidia in rows. C, a conidium with 

 its protoplasm divided. Z>, contents of conidia escaping as swarm-spores (zoospores). 

 E, 8warm-sj)circs (zoospores), with cilia. F, germinating swarm-spores. G, two swarm- 

 spores, up, germinating on a stoma and penetrating it. //, a swarm-spore, sp, of the 

 potato disease ( I'IT >iu><i>ar<i vifi^uix) penetrating' the epidermis of the potato stem; 

 e, i, epidermis cells. X 400. After De Bary. 



Peronospora by the mycelium inside the host producing 

 branches, which protrude through the stomata into the air ; 

 here their tips become enlarged, and finally separated by par- 

 titions from the remaining parts of the hyphas, thus forming 



