CHIFF-CHAFF 
is especially striking; sitting in a very upright position he 
raises the feathers on his head and back, the latter being 
thus much rounded, throws his breast feathers forward, 
swells out his throat, carries his wings rather loosely, giving 
himself the appearance of a round ball of feathers, spreads 
out his tail as far as possible and moves it sideways very 
slowly; this latter feature is curious, for he never at other 
times moves his tail in this way, herein differing from such 
birds as the Red-backed Shrike (Lantus collwrio) and Redstart 
(Ruticilla phenicurus), who habitually make use of this side- 
long motion when excited. 
During the period of courtship the males are apparently 
very quarrelsome, but the possession of the female does not 
appear to be the direct cause of their battles; perhaps they 
are not battles but only games; this is most difficult to 
decide, for they are frequently so vigorous that the impression 
left on one’s mind after watching them is that of a severe 
fight. Their flight when pursuing one another is very quick, 
entirely different from their ordinary one, and the way they 
dart in and out of the trees is quite amazing, the pursuing 
male as he flies often uttering the two notes, of which his song 
is composed, very quickly; and at other times both pursuer 
and pursued use the same buzzing note as during the court- 
ship. The actual fight generally takes place in the air, the 
clicking of their bills as they meet one another being quite 
loud. When standing close to them during these struggles 
they have sometimes fallen within a few feet of me, and as 
they tumble, locked together, through the air, twisting slowly 
round and round, they look like a mass of feathers devoid 
of all form; upon reaching the ground they le for a few 
seconds exhausted or surprised, then fly quietly away, each in 
his own direction. 
Nidification commences about the middle of April, soon 
after the courtship has taken place. The exact time varies, 
and the rapidity with which the nest is built varies corre- 
spondingly with it; sometimes the nest is commenced in a lazy 
15 
