Widmann — A Preliminary Catalog of the Birds of Missouri. 133 



man, no hollow trees can have afforded the security which an 

 unused chimney of a dwelling gives, inaccessible as it is to nearly 

 all the former enemies in the woods. It is this abundance of 

 safe nesting sites which accounts for the enormous increase of 

 Swifts since they became Chimney Swifts, and which allows of 

 a steadily growing extension of their breeding range into formerly 

 uninhabited regions. With his rare gift of daring, which enables 

 the Swift to penetrate deep into the chimneys of occupied houses, 

 he couples a great amount of sagacious caution as shown when 

 placing his nest into chimneys which he has reason to believe 

 will be used occasionally. I have repeatedly found nests placed 

 a short distance below the mouth of the stove pipe, though 

 eight and more feet from the mouth of the chimney, an expedient 

 of great advantage in case of a short period of unseasonable fires 

 in the stove. The first Swifts of the season reach Missouri 

 in the southeast in the last days of March (March 28, Butler Co.) 

 and St. Louis a week later (April 2, 1888, April 3, 1887, earliest 

 record March 31, 1885), but these forerunners are so few that the 

 best, perhaps the only, way to find them is to watch in the evening 

 one of their chimneys used for common roost. We have records 

 of their arrival during the first week of April not only from St. 

 Louis, but repeatedly from Fayette and once even from Keokuk 

 (April 7, 1897), but the Swifts are not generally seen before the 

 second week and become common only after the middle of the 

 month, usually during the third week. From April 20 to May 

 20 the common roost is not only used by the Swifts of the neigh- 

 borhood, but also by varying numbers of transient visitants 

 exceeding many times that of the summer residents. By May 

 20 the rush of north-bound guests suddenly subsides, but strag- 

 glers continue to the end of the month. May and early June, 

 the time of mating and wooing and noisy excitement, and of 

 the presence of troops of transients, is the time when they 

 are most conspicuous contributors to the animation of our 

 landscape. When incubation begins the Swifts, seen before 

 always flying noisily in twos or threes or little troops, all 

 at once fly singly and in silence. This period lasts until the end 

 of July or into August, when the young are on the wing and noise 

 and bustle begin anew, kept up chiefly by the youngsters, 

 which are at this time of the year easily distinguished from their 

 parents by the perfect, unbroken outline of their pointed, long, 

 strongly curved wings, while the parents show decided signs of 

 wear and moult, having shed certain of the primaries. As the 



