3 
It appears doubtful if, when fully adult, the bird ever loses the yellow underparts at any season; for 
male specimens shot in November and December in India differ merely from birds in full breeding- 
dress in having the entire plumage duller, the underparts rather paler, the blue-grey on the crown 
somewhat obscured by greenish, and on the breast there are a few dark markings. A male from 
Stockholm, shot on the 15th of September, and marked by Mr. Meves as being an adult bird, resembles 
these, but is somewhat duller in colour, has the eye-streak washed with primrose-yellow, and the under- 
parts are paler—which, however, may only be the effect of climate, as the differences are very slight. 
The extent of white on the throat in different specimens varies greatly ; but these variations appear to 
be individual. 
ScaRcELY any group of birds vary so much as the Wagtails; and it is barely possible to say with 
any degree of certainty which should be considered distinct species and which mere varieties. 
After a most careful examination of a very large series of specimens from various localities 
in Europe and Asia, I find it most difficult to arrive at any definite conclusion; but it appears 
to me that they naturally separate into four fairly distinct forms, which to a large extent have 
separate breeding-haunts. ‘These forms, Motacilla flava, Motacilla viridis, Motacilla melano- 
cephala, and Motacilla raii, 1 find it most convenient to treat as distinct species, though at the 
same time I feel bound to add that although the males in full plumage are almost always 
distinguishable at a glance, yet one not unfrequently meets with immature examples which it is 
hard to determine to which species they should be referred. Messrs. Finsch and Hartlaub, in 
their well-known work on the ornithology of East Africa (Vog. Ost-Afr. pp. 268-274), go most 
carefully into this question, and end in uniting all the above four species under the name of 
Motacilla flava—a course which, however, I deem it most expedient not to follow. 
The present species (Motacilla flava), which may be considered the typical form, is during 
the breeding-season found in Central Europe, whereas in the high north Motacilla viridis alone 
occurs, in the south one meets with Motacilla melanocephala, and in the west or north-west 
Motacilla rai is the predominant form; but during the winter and in the seasons of passage one 
finds all four species in the same localities in many parts of Southern Europe and Asia or in 
North Africa, as all migrate southward after the breeding-season. 
The present species inhabits during the breeding-season the central portions of Barone and 
Asia, being but rarely met with in the more northern portions of the Continent. It has occa- 
sionally been met with in Great Britain, but is only a rare visitant, Motacilla raii being the 
predominant species of Yellow Wagtail in our islands. Professor Newton says (Yarr. Brit. Birds, 
i, p. 060) that the first recorded occurrence in Great Britain was that of a fine adult male shot 
at Walton-on-the-Naze, on the 3rd October, 1834, by Mr. Henry Doubleday. Another was 
recorded by Sir Patrick Walker in January 1836, as having been obtained on the banks of the 
Water of Leith; and a third was said to have been met with near Edinburgh about the same 
time. A male was shot on May Ist, 1836, near Newcastle-on-I[yne; and on the 2nd May, 1836, 
Hoy killed an adult male at Stoke Nayland, in Suffolk, ‘The male figured in Yarrell’s ‘ British 
Birds’ was taken near Finsbury in April 1837. Besides these occurrences there haye been many 
others since Mr, Gould’s discovery (in 1832) that our British species and the present Yellow 
Wagtail are distinct; and Professor Newton says that nearly forty occurrences have on good 
authority been recorded. They have, he says, ‘generally occurred on or near the coast of the 
25 
PASy 
