220 Scientific Proceedings, Royal JDubtin Society. 



season. As soon as the second brood becomes strong enough on 

 the wing, the different famihes leave the more open parts of the 

 prairie and betake themselves to some suitable clump of trees in 

 the neighbourhood where they pass the night, making daily ex- 

 cursions to the surrounding country in search of food. In such 

 places several hundred will collect nightly, and before retiring to 

 roost occupy some time in desultory flights, pursuing one another 

 hither and thither, and frequently ascending to a great elevation, 

 from whence they return by a rapid and headlong rush, accompa- 

 nied by a peculiar whirring noise made by their wings, which can 

 be heard at a considerable distance. They are excessively graceful 

 in all their motions, and their flight is lighter and more buoyant 

 than any other bird with which I am acquainted. Their food 

 consists of bees, moths, beetles, small grasshoppers and other 

 insects, all of which are caught in the air. Although their ordinary 

 note is harsh, even during the breeding season, they have a habit 

 during the fall of singing in concert, most frequently before retiring 

 to rest, with a clear musical, but faint warble, which is very 

 pleasing, when, as is usual, a large number are engaged at the same 

 time ; and these notes are not confined to the males, but females 

 and young seem likewise to participate in this evening hymn. 

 They fearlessly attack any predatory birds, such as ha^s^ks, and 

 crows, which may venture into their haunts, and not content with 

 showing their dissatisfaction by angry cries alone, use their beaks 

 also with such effect that the marauder is quickly put to flight. 

 The greater number leave this district during September, but small 

 straggling flocks, composed entirely of adult males, linger in 

 sheltered localities until the end of the following month. The 

 stomach of a specimen obtained in the fall contained grapes and 

 snowberries, but this was the only instance in which I found traces 

 of vegetable food. 



Tyrannus carolinensis (Linn.) King-bird. — A common 

 summer visitor to the thinly wooded portions of the county, 

 arriving about the middle of April ; mesquite flats along the edges 

 of the denser timber, and wooded creeks, are the favoured haunts 

 of this bird, especially where a few large isolated trees are inter- 

 spersed at intervals, their nests being very frequently placed among 

 the upper branches of these. In the spring they arrive always 



