vi BRITISH GALLS 



definitely limited. It is, in fact, one of the chief charms 

 of the study of galls that it brings us face to face with 

 life processes in general, and with the very varied modes 

 of activity manifested by living material under different 

 conditions. They are an epitome of biological facts. 

 Some of these are very simple and others complex, but 

 in no department of our subject are we allowed to 

 forget that we have to deal with the activities of life. 

 The breadth of the subject is, indeed, to most minds 

 one of its chief attractions. 



The student of entomology having identified the 

 varied forms of fly, moth, and beetle, each in their varied 

 stages, which concern themselves in gall production, 

 finds himself at once obliged to recognize also the differ- 

 ent proclivities of growth tendencies, not only of different 

 plants, but of different parts of the same plant, and 

 becomes a student of botany in its several departments. 

 There is, however, no limitation in our topics, for having 

 obtained a good insight into both botany and entomology, 

 the observer will soon become convinced that, in addi- 

 tion to them, he is obliged to study and recognize the 

 ever- varying influence of seasons and weather. We may 

 anticipate for the study of galls that it will soon become 

 one of the most attractive and fascinating branches of 

 natural history. It lends itself to the collector with 

 especial attractiveness, for many kinds of galls are very 

 easily preserved, and a series should form part of the 

 possessions of every student. It is at once easy and 

 difficult ; easy as regards its principles, but full of detail 

 as regards their application. 



In the formation of a " spangle " on an Oak leaf, a 



