THE OSPREY. 11 



Tanagers and Rose-breasted Grosbeaks. A few Hawks, the Crow, and the 

 Turkey Vulture were often seen. 



The most interesting feature of the bird life was the migrating swarms. 

 Early in the morning troops of many species, of Warblers especially, were 

 flittering among and over the branches of the dwarf thick foliage of the oaks 

 and chestnuts while other bands, largely Robins, Flickers and CJhewinks, were 

 common in the more open bushy places. These last were mostly adults. 

 Frequently the troops of Warblers seemed clustered in the vicinity of one or 

 two. White- breasted Nuthatches, who were somewhat noisy, but aside from 

 a few young Warblers who would now and then utter an effort at a song or an 

 occasional squeak, the woods were silent. The general direction of the birds' 

 flight was toward the southeast, that is, diagonally across the mountain mass 

 toward and south of the rising sun. After 10 to 11 a. m. a few of these birds 

 were seen as the troops had evidently started on the day flight and had doubtless 

 scattered over the lower areas far to the southeast. These birds from the far 

 north were constantly passing while the summer residents, some of them at least, 

 and these nearly all immature, were moulting into the first teleoptile plumage. 



The following facts are closely connected with the migration of birds on 

 Stony Man Mountain, and may be of interest on the general subject. 



At daylight, with little or no wind, all the valleys as far as the eye could 

 see, both to the east and west of the Blue Ridge, were covered with a dense fog 

 the surface of which was about 2,000 feet above sea level and thus some 1,000 

 feet above the valley areas. At the same time the mountains from above 

 2,000 feet, approximately, stood out bold and clear against a rather dull sky 

 with no sign of clouds. By 8 o'clock, however, the rising sun had affected 

 the cloud surface so that it became rapidly dissipated, and spreading, drifted 

 off the depressions of the mountain sides and soon filled all the lower levels, 

 and eventually the mountain tops. By 10 or 11 a. m. a rising breeze would 

 drive away the fog so that with a bright sun the mountains and valleys were 

 clear, except for the haze in the distance. 



With an eastern or western breeze early in the morning the fog would be 

 driven in the opposite direction up the mountain side and then pass off as 

 clouds high above the valley. It was not determined how the mountain fog 

 on these windy mornings affected the abundance of birds at daylight for these 

 facts were not established until considerable time had elapsed, and time was 

 not available then to determine the matter, but this much was established, that 

 when the Shenadoah Valley to the westward or northward, and southward as 

 far as could be seen from an elevation of 3,600 feet was covered with a dense 

 cloud and the mountain tops were clear — migratory birds were abundant. 



We may be sure that when these birds descended from their night flight 

 they necessarilly alighted where they could see trees, we can hardly accept the 



