em Illinois the nesting houses are habitually shared with the last named species, 

 and the birds seem to have reached a modus vivendi on peaceable grounds. 



At the end of the breeding season the Martins are no longer confined to the 

 nesting site, but range freely by day, and gather in large companies to roost at 

 night. Sometimes the ridge or cornice of a building is used for this purpose, 

 but oftener the birds resort to some unfrequented woodland or out-of-the-way 

 place. In the summer of 1901 we saw upwards of a thousand of them roosting in 

 the hackberry trees of North Harbor Island, and had reason to believe that the 

 company represented not only the entire population of the Lake Erie Islands, but 

 a considerable number from the Canadian and Ohio mainland as well. 



1. Martins prefer a house in the open where the flight is not obstructed. 



2. The house should be about fifteen feet high. 



3. Rooms should be not less than 5x5 and 6 inches high nor more than 6x6 

 and 7 inches high. This latter is the Jacobs standard. 



4. Rooms should have tight joints. No cracks. 



5. Doors should be 2^ inches square or 2^4 inches in diameter if round. 



6. Doors should be one inch above the floor and as far apart as possible. 



7. The house should be taken down or closed when the Martins leave it. 



8. The house should be put up or opened the last week in March. 



9. The house should be get-at-able, either by ladder or by making the 

 pole so as to lower easily. 



10. Perches or porches are desirable, the Martins like to sit about the door- 

 ways. 



11. As all swallows hunt over water, the vicinity of water is the best place 

 for a box. 



Some Beneficial Birds and Their Protection 



By J. P. Gilbert 



The most important enemies to crops are undoubtedly the insect and rodent 

 pests. Insects with their poorly constructed digestive organs eat enormous quan- 

 tities of food but really digest only a small part of what they eat. It is said to 

 cost the farmer twice as much to feed our insect foes as it does to run our public 

 schools. Mice, rats and other rodents gorge themselves upon grasses and grains, 

 and often cut to pieces and waste far more than they eat. Rats alone are said to 

 destroy one hundred million dollars' worth of property in the United States 

 each year, and mice of all kinds, perhaps, do even more damage than do the rats. 

 These rodents all multiply with alarming rapidity and if not held in check might 

 almost bring on a national calamity. 



It is doubtful if anything else is so important as hawks and owls in checking 

 outbreaks of destructive rodents. To keep up their high body temperature and 

 to produce the immense amount of energy needed on their hunting expeditions, 

 birds of prey must devour surprisingly large quantities of food. With but very 



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