114 University of California Publications in Zoology. (Vou.5 
I several times saw what I thought a significant performance: an 
adult bird apparently resenting vehemently the food-petitioning 
advances of immatures, flying at them and driving them off. 
Perhaps this discouraging procedure on the part of the parents 
hastens the early departure of the young, which then invade 
beyond the confines of their birth-loeality, in search of new 
forage. 
Adults were beginning to moult July 24. The first young out 
of the nest were seen on the upper Santa Ana in 1906 on July 8; 
and in 1907 on July 3. The young have a loud impatient twit- 
tering call, which they utter as they follow their parents about, 
and this note readily calls one’s attention to them. Audubon 
warblers were common around Bear lake, and the meadows in 
Bear valley, July 28 to August 3, 1905, but were not seen in the 
pinyon belt or anywhere on the desert slope of the mountains. 
All over the north slopes of Sugarloaf, from the summit, 9800 
feet altitude, down to the cienaga at the north base, 7500 feet, 
Audubon warblers were numerous, August 19 to 23, nearly all 
then being in full winter dress. <A series of fifty-one specimens 
of this species was obtained to show moults and plumages. 
Dendroica nigrescens (Townsend). 
Black-throated Gray Warbler. 
This warbler appeared to be confined exclusively to the golden 
oak belt during the breeding season. It was first met with in the 
lower Bear ereek cafion near its confluence with the Santa Ana, 
June 12, 1905, when a nest with young was found. In the vicin- 
ity of Seven Oaks the species was very common and in full song 
June 13 and 14. In the same locality July 7 to 12 families of 
moulting adults and young were frequent. A pair were seen on 
the south side of Sugarloaf in a tract of golden oaks June 24, 
1905, and others in the same vicinity July 11, 1906. By the last 
of July birds-of-the-year began to seatter out generally over the 
mountains. They appeared commonly along the upper Santa Ana 
by July 24, 1906. One was taken at Bluff lake July 25, 1905, 
and many were seen around Bear lake July 31 to August 2. 
They were frequently met with in the pinon belt about Doble, 
