RUSTS. 123 



butter-bur, and the latter on those of the harebell 

 and other Gampanulce, less frequently. We have, 

 however, indicated sufficient, since their great simi- 

 larity in unprofessional eyes will furnish, in one or 

 two species, all that is desirable for the micro- 

 scopist. 



Unless some similar plan to the following be 

 adopted for examining the species of this genus, 

 it may result in disappointment; for the slight 

 attachment of the joints to each other will other- 

 wise present only a mass of simple echinulate 

 cellules, if a portion be only removed from the leaf 

 on the point of a lancet. This method consists in 

 making a thin vertical section of a pustule in which 

 the spores are contained; by this means the arrange- 

 ment of the fruit and the mucedinous threads from 

 whence they proceed may be observed. Any per- 

 son possessed of the cardinal virtues of microscopy 

 — patience and perseverance — will be rewarded in 

 this instance ; whilst those who are deficient will 

 lose an object worthy of the virtues they dare not 

 boast. But few instances have occurred in this and 

 the preceding chapters in which the exercise of any 

 great ingenuity or application has been called for ; 

 the most juvenile or truest tyro at the microscope 

 may see for himself much of what has been 

 indicated, whilst a few opportunities have occurred 

 for more practised manipulists to prove that they 

 are neither juveniles nor tyros. 



