No. 4.] BIRDS USEFUL TO AGRICULTURE. 53 



that certain hens habitually break and eat eggs. Undoubt- 

 edly individuals among birds have a similar habit, and it 

 will crop out sometimes where least expected. It cannot be 

 doubted that catbirds, wrens and cuckoos occasionally have 

 this habit, as do jays and crows. Even the Baltimore oriole 

 — a member of the family we are now considering — has 

 now and then been seen to attempt to destroy the eggs of 

 other birds. That it sometimes succeeds is shown by the fol- 

 lowing note from Mr. Mosher : "Monday, June 12, 1899: 

 While making observations on a pair of rose-breasted gros- 

 beaks, my attention was called to the cries of two male 

 orioles. They were having a pitched battle every few min- 

 utes. On going to the spot, I found that one of the males 

 was fighting the other away from the nest, which was in the 

 top of a small birch. The bird that owned the nest would 

 perch just above the nest and keep guard. In a few minutes 

 the other would make a rush at the nest from a neis'hborino' 

 tree, and they would grapple and sometimes come nearly to 

 the ground. They kept this up all of the three hours I was 

 near them. The bird without a mate went to a redstart's nest 

 that had two eggs in it, and, taking the eggs in his bill, 

 threw them out of the nest to the ground. He then attacked 

 the nest, using his beak and feet, and exerting his strength to 

 the utmost, until he had tipped the nest out of the crotch and 

 it fell to the ground. Then he went back to the trees near 

 the other orioles. Tuesday, June 13, 1899 : An oriole, 

 probably the same observed yesterday, went to a red-eyed 

 vireo's nest and threw out one of the eggs, and would prob- 

 ably have thrown out the others if the vireos had not 

 attacked him and driven him ofi". " 



With the oriole this habit so far as observed has been con- 

 fined to male birds which were probably unmated. It may 

 be a mere eccentricity. The oriole is certainly one of our 

 most useful birds. It is a great destroyer of the canker 

 worm and tent caterpillar. It is, in fiict, an inveterate feeder 

 upon caterpillars and other orchard pests. It also eats 

 great numbers of grasshoppers, injurious ])ugs and beetles. 

 Wire worms are also eaten liy it. The farmer should not 

 only welcome the oriole, but furnish it with nesting material 

 and fruit if necessary. 



