42 MICROSCOPIC FUNGI. 



globular protuberances intermingled witli them. 

 These soon rupture the epidermis^ and take the 

 orange colour and cylindrical form of cluster-cups 

 {JEcidium). At length the summit of the peridia 

 opens to allow the escape of the stylospores. It is 

 easy to assure oneself that the spermogones and 

 cluster-cups proceed from the mycelium of the 

 sporidia which had been sown. During several 

 days the length and number of the peridia of the 

 j^cidium continue to increase. One month after 

 sowings brownish or blackish points make their 

 appearance upon the whitish spots^, around_, or 

 intermingled with the cluster-cups. These increase 

 rapidly in number and magnitude. Examined by 

 the microscope^ they present the ordinary fructi- 

 fication of UromyceSy mingled with stylospores. 

 Thus the mycelium of the cluster-cups engenders 

 at the end of its vegetation fruits equal in all points 

 to those from whence they are in the first instance 

 derived. 



The stylospores of the cluster-cups possess the 

 irregular_, globular form and structure of their 

 congeners. They are filled with orange granular 

 matter^ and provided with a colourless^, finely- 

 punctated epispore. When these stylospores ai*e 

 sown on the moistened epidermis of a favourable 

 plants the germ-tube at first creeps along the 

 surface^ but as soon as its extremities find a stomate^ 

 it enters it and elongates itself in the air-cavity 

 below the orifice^ receives the contents of the original 



