4a MICEOSCOPIC FUNGI. 



globular protuberances mtermingled with them. 

 These soon mptnre the epidermis, and take the 

 orange colour and cyHndrical form of cluster-cups 

 [Mcidiuw). 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 mycehum of the 

 sporidia which had been sown. During several 

 days the length and number of the peridia of the 

 ^cidium continue to increase. One month after 

 sowing, 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 Uromyces, mingled with stylospores. 

 Thus the mycehum of the cluster-cups engenders 

 at the end of its vegetation fruits equal in aU points 

 to those from whence they are ia 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 are 

 sown on the moistened epidermis of a favourable 

 plant, 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 



