4^0 Scott ou the Birds of Arizona. [October 



with this speiecs was curly in October, 1SS4, on the San Pedro slope of 

 the Catalina Mountains, at an altitude of 3000 to 4000 feet. From the 2d 

 to the 6th of the month they were rather common, from a dozen to twenty 

 being noted each day. The birds are, as far as I am aware, very like the 

 common Chimney Swift in general habits and flight. Mr. Allen has xevy 

 kindly identified the species for me, from a female (No. 996) taken Octo- 

 ber 2, 1SS4, in the locality above mentioned. 



97. Micropus melanoleucus. Wiiite-thkc^ated Swift. — An abundant 

 migrant, and a few probably occur in winter. I have no positive I'ecord of 

 its bi-eedingin the area in question, but have constant records of seeing the 

 species in the Catalinas, from the middle of March until August. The 

 bird is probably most abundant about the middle of May in the vicinity of 

 Tucson, at which time I have seen them by hundreds. Here at this sea- 

 son they do not appear to have the habit of high flight so noticeable in 

 Colorado and at other points where I have met with them, but are to be 

 seen skimming low over ponds, and even close to the ground, in pursui 

 of insects, anil (piite as tame and unsuspicious as the Chimney Swift of the 

 East. That a few are winter fesidents there can be little doubt, as my 

 records mention them every month in the )ear, save February, either in 

 the Catalinas or near Tucson. On January 5 of the present year, which is 

 about midwinter in this region. I saw five in the foothills of the Cata- 

 lina Mountains, at an altitude of about 3500 feet. 



9S. Trochilus alexandri. Black-chinned IIiimmingbikd. — A com- 

 mon summer resident in the Catalina Mountains, where it breeds very 

 commonly. Arrives early in March, and is abundant by the last of that 

 month. By the last of April the birds are mated and begin breeding; and 

 I have found nests with fresh eggs late in July and early in August. By 

 the loth of October they have all left the region in question. 



Though I have found many, at least a hundred, Iliunmingbirds' nests in 

 the Catalinas in vicinity of m>' house, and have been very careful to iden- 

 tify the owners, and though most of the species to be presently mentioned 

 ai-e quite as abundant as Trochilus alexandri., and though two at least (/. 

 latirostris and T. cosfa;) are present all the time that T. alexandri is 

 found, yet ] have no positive record of any other Hummingbird breeding 

 in this immediate locality. 



I have not found this species to be of common occurrence above 7000 

 feet altitude in the Catalina Mountains. It is common and breeds in the 

 neighborhood of Fort Lowell, which is North of Tucson, and lies at about 

 the same altitude, but Mr. Brown regards it as rare about Tucson, and 

 has no record of its breeding there. 



99. Trochilus costae. Costa's Hummingbird. — My first acquaintance 

 with this species was made at Riverside in April and May, 1S82. The 

 birds were not very common there, but were the only Hummingbirds ob- 

 served. On May 5, 1SS2, I found a nest, the female sitting, and the very 

 conspicuous male in close attendance, often perching on a twig but a few 

 inches away. This nest was built in a cottonwood tree, almost at the ex- 

 tremity of one of the branches, and about thirty-five feet from the ground. 



