OF EASTERN PENNSYLVANIA. 1 97 



abundant in our latitude, and is chiefly a denizen 

 of eminently rural districts, where it breeds in 

 small numbers in the excavations of the Bank 

 Swallow, but more generally between crevices in 

 walls and arches of bridges over running water; 

 in some instances, less than a, foot above the sur- 

 face. It arrives about the 20th of April; but in 

 very backward seasons, as late as the 5th of June. 

 During its early visit, it delights in the retirement 

 of solitary streams, and then manifests consider- 

 able shyness. Its chief concern is the procure- 

 ment of food. 



Whilst foraging it is not so strictly aerial as the 

 Barn Swallow, but has been observed on several 

 occasions to glean among the foliage and branches 

 of trees, but very rarely upon the ground. Its food 

 consists principally of dipterous and lepidopterous 

 insects, with a small percentage of coleoptera. 

 Remains of the following insects have been found 

 in the many stomachs which we have examined : — 

 Anthrax elongata, Tipula ferruginea, Culex 

 taniorhynchus, Tabaniis lineola, Stomoxys calcitrans, 

 Syrphus obliquus, Musca ccesar, and snialler diptera 

 which inhabit aqueous situations; common May- 

 fly ^ and other small neuropterous , beings, and 

 ' Spilosoma Virginica, S. acrcea, Orgya leucostigma, 

 Utetheisa Bella, Colius pkilodice, the smaller 

 Argynni, with the most common of the Lycanidce, 

 Noctuidce, and Tortricidce. 



Its flight resembles that of the Bank Swallow in 

 being less firm and sustained than thaX oi Hirundo 

 horreorum. 



