﻿PREFACE. 



The value of the benefits conferred by Birds on Agriculture is 

 fortunately generally admitted, and no apology is needed for 

 efforts to facilitate the recognition of some of the best friends of 

 the farmer, at a time when the conservation of our food-supplies 

 is a matter of National importance. In recognition of this fact 

 the Trustees gave instructions for the preparation of an exhibition, 

 in the Central Hall of the Museum, of a selection of the species 

 believed to be beneficial to Agriculture, and for the simultaneous 

 issue of a small Guide-book, in further illustration of the subject. 

 The work was entrusted to the well-known Naturalist and Artist, 

 Mr. F. W. Frohawk, and his summary of the subject is given in 

 the following pages. 



The magnitude of the effect produced by Birds in the destruc- 

 tion of injurious Insects is illustrated by one or two of the actual 

 exhibits, which show the entire contents of the crop or stomach 

 of individual Birds ; consisting, in the instances selected, of an 

 enormous number of Insects which are known to be highly 

 injurious to cultivated plants. Numerous Birds are entirely 

 insectivorous, while many others destroy immense numbers of 

 Insects during their nesting period, when their young are fed 

 exclusively on food of this nature. Even the House- Sparrow, 

 which may be injurious by consuming large quantities of corn, 

 nourishes its young on Insects. Other species may be beneficial 

 by eating the seeds of troublesome weeds. 



It will be understood that both the exhibition and the Guide- 

 book include merely a few of the species which might have been 

 included, and that the selection consists of Birds which may fairly 

 be considered beneficial. But the decision of the economic status 

 of a given species is often a highly complex problem, as is 

 explained by the author in his introductory remarks. It will be 

 sufficient to point out here that a Bird such as the Starling may 

 be beneficial under certain conditions and when not too numerous 

 in individuals, but that if its numbers increase beyond a certain 



