EUSTS. 121 



together in tlie pustule is sliown in plate VIII. 

 fig. 182^ from an allied species. When these spores 

 germinate^ which they do with great readiness^ each 

 division emits a long tube_, which generally remains 

 simple and undivided^ and from its extremity is 

 produced a reproductive body of an obovate or 

 nearly kidney-shape. These filaments are about 

 Y^-oth of an inch in lengthy of a colourless tran- 

 sparent membrane^ along which the orange-red 

 contents of the spores pass into the newly-formed 

 sporidia_, or reproductive bodies by which they are 

 terminated. Most of these reniform sporidia dis- 

 engage themselves from the filaments on which they 

 are produced^ and either elongate themselves into 

 a simple and uniform filament^ or swell at the 

 extremity as if to reproduce a second spore. If the 

 newly-formed sporidia do not become free^ they 

 increase the length of their primitive filament^ 

 which by a frequent repetition of the process 

 becomes a tube swelling out at unequal distances. 



The summer spores^ or pulverulent spores of the 

 first generation_, which are analogous to the Uredo- 

 spores of Areginay are also capable of germination^ 

 for^ if placed in favourable circumstances^ they will 

 develop very long filiform processes^ which either 

 remain simple or become more or less branched, 

 but always nearly uniform in their diameter. M. 

 Tulasne states that he has observed this germina- 

 tion many times, though we have been less for- 

 tunate. 



