354 BULLETIN 17 6, UNITED STATES NATIONAL MUSEUM 



different times, and, at each stop at the apex, the flopping of wings was 

 indulged in, after which the bird again sought his perch on the cottonwood 

 above his mate. I was close enough almost to hear his wing beats as he sped 

 to and fro, and I watched the p'air for three minutes, when they both flew 

 off of their own will, without being disturbed. At no time during the minute 

 and a half duration of the nuptial flight was there any vocal demonstration, 

 though both birds were rather vociferous when perched. 



Mrs. Bailey (1923) saw some "giving their aerial courtship dance 

 from among the mesquites. One that I watched varied the usual 

 triangiilation by first flying back and forth horizontally across the 

 face of a bush, then making narrow Vs with the point at the bush, 

 followed by wide-sweeping swings out over the mesquites as if from 

 pure spirits.-' 



Eobert S. Woods (1927b) writes: 



The shuttling of the Black-chinned Hummingbird, which follows a path 

 like a narrow figure 8 lying on one side, has often been mentioned in accounts 

 of the species. Its other form of nuptial flight most closely resembles that of 

 the Rufous Hummingbird, just described [a swooping dive, punctuated at the 

 bottom of its course by what might be described as a tremulant squeak or a 

 rapid sucession of about four thin, vibrant notes], but the vocalization is more 

 prolonged and of rather different character — a long-drawn, pulsating, plaintive, 

 liquid note, probably the most pleasing utterance of any of our Hummingbirds. 

 The heavy droning sound of its flight, so noticeable in the shuttling movement, 

 is heard in this case only while momentum is first being gained on the down- 

 ward swing. The shuttling flight, it may be noted, is practiced almost solely 

 by those species in which the wings of the male are specially modified for 

 noise-making purposes. 



Nesting. — Major Bendire (1895) gives a rather comprehensive 

 account of the nesting of black-chinned hummingbirds, and I cannot 

 do better than to quote his remarks. He says : 



Throughout the greater part of their range, it rarely begins laying before 

 May 1, and the season is at its Tieight through this month, while second or 

 possibly third sets are found up to the latter part of July, and occasionally 

 still later. The nest is readily distinguishable from that of the Ruby-throated 

 Hummingbird by not being covered on the outside with lichens. It is com- 

 posed of plant down, varying in color from white to buff ; the latter is obtained 

 from the under side of the young leaves of the sycamore, the former probably 

 from willows, milkweed, or thistles. These materials are well worked together, 

 and the outside of the nest is thickly coated with spider web. In an occasional 

 specimen a small leaf or two, or a few flower blossoms of the oak are worked 

 in the outer walls. In a specimen from Marfa, Texas, the outside is well 

 covered with small flower spikes, the male aments of a species of oak, hiding 

 the inner lining completely. 



He mentions a beautiful nest that "is mainly composed of white 

 willow down, mixed on the outside with a few small leaves and the 

 scales from the willow buds." 



These are firmly held in place by an abundance of spider web, with which 

 it is also securely attached to the little fork in which it is saddled. The 



