426 NORTH AMERICAN BIRDS. 



tlio crevices of rocks, and tliat their eggs are pure white, and of an elongated 

 form. 



Dr. Cones found this species rather sparingly distributed throughout Ari- 

 zona, always in the neigliborhood of clifl's and precipices, wliicli it exclu- 

 sively inhabits. From Inscription liock, about one day's march from 

 Wliipplc's I'ass, to tlio San Francisco Mountains of Arizona, he found these 

 birds in great numbers, except along the valley of the Colorado Chicjuito, 

 where tliere were no suitable cliHs for their habitation. He generally found 

 thom congregated in considerable, sometimes in immense, numljers in the 

 vicinity of iiuge clitl's and piles of rocks. Their note, he adds, is an often and 

 quickly repeated twitter, loud and shrill, and quite different from that of 

 the C. iKlagica. lie states that they build their nest ui)on the vertical I'acea 

 of precipitous rocks. 



Dr. Woodhouse met with a Swift in the same region referred to by Dr. 

 Cones, which he called Accnithj/lis sa.rati/is, which may possibly be the same 

 species, but of which no specimen was procured. Tliey were breeding in 

 tlie crevices of the rocks. The description, however, does not at all corre- 

 spond. 



This species has lately been met with by Mr. Salvin, in Guatemala, where 

 it is by no means common, and so very local that its presence might readily 

 have been overlooked. He found it near Duefias, in a gorge witli precipi- 

 tous rocks on the rigiit hand, along the cour.se of the river Guacalate. His 

 attention was drawn to a noise coming from the rocks, which he at first took 

 to be bats in some of the cracks. After watching for some time, he saw two 

 Swifts dart into a crack in the rock twenty feet from the ground, and the 

 noise became louder than before. I'esorting to several expedients, in vain, 

 to make them Hy out, he climbed up part way, and there found one of them 

 killed by a random shot of his gun. Another discharge of his gun brought 

 out five or six more, which were immediately imrsued by the Coti/lc scrri- 

 jh'miii^. He obtained .thren specimens in all. Jhe spot was evidently their 

 common roosting-place, and by the noise they made he judged they were 

 there in large numbers. He found them about the middle of February. 



Dr. Coo])er met witli this species near Fort Mohave, but saw none before 

 ^lay. On the 7th of June, near the head of Mohave lliver, lie found a few 

 about some lofty granite cliffs, and succeeded in obtaining one. Their flight 

 was exceedingly swift and changeable, and tliey were very difficult to shoot. 

 He also found them about some high rocky bluffs close to tlie sen-shore, 

 twelve miles nortii of San Diego. They were seen tlij ^.st of March, but 

 may have been there for a montli jireviously. 



Mr. Alien encountered this little-known Swift near Colorado City, where 

 it was quite numerous alwnt the higli cliffs in the "(Jardenof the Gods," 

 and of wliicii, with great difficulty, he procured four S])ecim('ns. It was 

 nesting in inaccessible crevices and weather-beaten holes in the rocks, about 

 midway up the high vertical cliffs, some of which were not less than three 



