108 MicRosconc fungi. 



mycelium as that of tlie rose rust^ the rose brand is 

 afterwards developed ; whilst from the nidus of the 

 bramble rust (plate III. fig. 40) the bramble brand 

 is also at length produced; and the successor to the 

 burnet rust (plate III. fig. 31) is the burnet brand. 

 Besides these^ a rust belonging to the same genus 

 may be found on the leaves of the poplar^ the spurge^, 

 and the common valerian^ and two or three species 

 on willows. It can scarcely have escaped notice^, 

 that the goat-willow is almost constantly afflicted 

 with a rust on the under surface of the leaves 

 (plate VIII. fig. 160). This species will again come 

 under notice as the summer spores of a truly 

 dimorphous species. 



One of the rusts separated by some botanists from 

 this genus is found (possibly most commonly) on 

 the leaves of the raspberry; but during the past 

 autumn we have met with it plentifully on the upper 

 surface of the leaves of one or two species of bramble^ 

 and have never seen it growing on the raspberry, 

 although in all descriptions of the species that is 

 stated to be its habitat. Even to the naked eye 

 this is so distinct, that no one could well confound 

 it with any other. It appears very late in the 

 autumn, and the spots are scattered at some dis- 

 tance apart from each other (plate YIII. fig. 162) ; 

 each spot or pustule forming a ring (plate VIII. 

 fig. 163 enlarged) encircling a cluster of spermo- 

 gones which occupy the centre. 



Another rejected species {Lecythea Lini, Lev.) 



