GREY-HEADED YELLOW WAGTAIL. 145 
to his mate with his soft and tender notes. There is 
much agility in all their movements, but they are ex- 
cessively timid, and are driven away by the least noise. 
Notwithstanding they are taken in numbers in Italy, 
where the pleasures of the table supersede any regard 
for the utility of these birds. The next is placed at a 
slight elevation on the ground, either among the grass 
or corn, and is formed of roots, blades of grass, and 
moss ; the interior is made soft and warm by wool. The 
eggs are four or five in number, and do not sensibly 
differ from those of the Yellow Wagtail.” 
The ‘^specific characters” by which this notice is 
headed, are those by which this variety may generally 
be distinguished, but they are by no means constant. 
Mr. Tristram has sent me two specimens of M. Jiava of 
Linnseus, (known to British naturalists by the name 31. 
neglecta, adopted by Gould and Yarrell,) shot in Algeria, 
one in May, 1856, the other in May, 1857. In the 
former the head is grey; the white mark extends from 
the posterior angle of the eye for five lines and a half, 
but not over it at all, and the throat is pure white. In 
the latter, a male, the white stripe extends as usual over 
the eye, but the throat, like the rest of the body, is 
yellow, with this exception, that the feathers at the hase 
of the under mandible, and a line separating the grey 
of the head from the yelloio of the throat, are white. 
These are evidently transitional varieties, and did they 
point to real structural changes, would be valuable 
supports of the natural selection theory. 
Of the adult male the top of the head, the nape, and 
cheeks are of a grey lead-colour; the back and rump 
bright olive green; throat, sides, and front of the neck 
pure white; rest of the under parts bright and deep 
yellow, having the flanks more or less olive green; wing 
VOL, II. 
X 
