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which incited their migration ; but as the frost breaks up, and 

 even before the thaw has actually commenced, we see a large 

 portion of these passengers returning to their worm and insect 

 food in the meadows, attended probably by many that did not 

 take flight with them." 



The services of the common Robin, as the guardian of our 

 fields and agricultural crops, are of such an indispensable 

 character, and so far exceeding those of any other bird, that I 

 feel constrained to devote a considerable portion of this essay 

 to his defence. A few years ago, the Horticulturists in the 

 vicinity of Boston, annoyed by the depredations of the Robin 

 upon their early fruits, petitioned the Legislature to strike out 

 the name of this bird from the list of those which are protected 

 by statute. The subject was referred to a Committee, who were 

 ordered to make inquiries and report upon it. Prof. J. W. P. 

 Jencks, Chairman of this Committee, has published in his 

 Keport some new and important facts, that clearly establish 

 the character of the Robin as one of the farmer's friends. 



The coui-se he pursued was to kill one Robin daily, and 

 carefully examine the undigested food which it had eaten. 

 From these daily examinations, not a particle of vegetable food 

 was found among the alimentary contents of this bird, from the 

 early part of March to the first of May. Insects of many 

 species, in all stages of growth and development, were its sole 

 food. Nine-tenths of the aliment collected during this period 

 consisted of one kind of larva — that of the Bibio Albipennis 

 of Say. Of this larva, from one to two hundred, in a fresh 

 condition, were frequently taken from a single bird. 



This fly, according to Dr. Fitch, comes abroad about the 

 ^Oth of May, and continues a little more than two weeks. It 

 is very common in fields of growing wheat, and probably lives 

 at the expense of this crop. It is found, however, abundantly 

 upon other vegetation, resting upon the leaves and flowers of 

 the garden, and in mowing lands and pastures. It may be 

 recognized by its frequency, its white transparent wings, and 

 its black body, clothed with soft white hairs. The larva of 



