NATURE STUDY IN SCHOOLS. 



195 



of the depletion of the roost has been completed in or- 

 der that three or four other boys might linger into the 

 twilight and gather a few cent's worth more of chest- 

 nuts. I will venture to say, to put it within bounds, 

 that each of those birds was worth at least a quarter 

 of a dollar a year to the citizens of this city as rn in- 

 sect destroyer. As we have stated that there were at least 

 7000 birds which came to the roost every night, it is 

 easy to estimate the loss incurred by their having been 

 driven away. And this loss might have been preven- 

 ted by the presence, in the roost or in its vicinity, of a 

 single policeman for an hour each evening. 



Since writing the above, Mr. Fitzpatrick informs me 

 that a few birds still continue to come into the roost, but 

 these are mainly grackles. On the evening of the twenty- 

 fifth I saw but live robins and no grackles and I remained 

 near the roost until after six o'clock. 



C. J. Maynaed, President. 

 Fig. 89. 



Bronzed Grackle. Massachusetts. 



