Plate XLI. 



PETROCHELIDON LUNIFRONS-Cliff Swallow, 



Cliff* Swallows arrive in Central Ohio about the beginning of the third week in April, and remain 

 until about the end of the first week in September. The nest is constructed the last of May or the first 

 of June, or even later if the season is cool and rainy. Two broods are frequently reared. 



LOCALITY: 



The nests are placed on the outside of a barn or other building, under the eaves or under some 

 projecting timber that will afford shelter. Only occasionally are they built in town. Generally they 

 are to be found under the eaves of an old barn in the country. In no other situation have I ever 

 observed them, but Dr. J. M. Wheaton has seen them upon an old mill, and also under the eaves of 

 a railroad depot at Georgesville. 



POSITION : 



The nest is adapted in size and shape to the place selected. Sometimes it is fastened to a sino-le 

 surface, and that perpendicular; but generally the side of the barn and the roof, or the projecting end of 

 a rafter, off'er two surfaces to which it is attached. Sometimes it is even attached to three or four 

 planes, and often the nests are so crowded together that a common wall divides two interiors. The dis- 

 tance from the ground depends upon the building selected. I have seen nests under a roof so low that 

 they could easily be reached, and again, under the gable end of the highest barn. 



MATEEIALS: 



The nest is constructed of mud alone. No straw, grass, or hair is worked into it, as in the nest of 

 the Barn Swallow. The clay, however, is collected in a similiar manner, and from similiar places, and 

 is worked in the same Wcxy, pellet after pellet being laid, one upon another, the construction progressing 

 from the surface of sui^port toward the doorway. The structure when complete is frail, possessing only 

 that strength which is natural to the clay of which it is made. It is difficult to detach them whole, and 

 even when detached, any thing but the gentlest handling will crumble and break them. Usually the 

 nests measure in width between four and a half and ^yq and a half inches; in height between three and 

 four inches, and in antero-posterior diameter between four and six inches. The walls are thin, commonly 

 one-fourth to three-eighths of an inch, thus leaving a large cavity within, the floor of which is generally 

 lined with a few straws, and sometimes feathers or wool. The externak outlines of the nests are often 

 irregular on account of the positions chosen. The entrance varies in diameter from one and a half to 

 two inches, and differs much in construction in different nests. Ordinarily, the opening is in the lower 

 half of the structure, and has a slight projecting rim below, which increases at the top so as to form a 

 little roof, thus ofi'ering additional shelter from beating wind and rain. Sometimes this projection is 



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