TAYLOR: D(>MINAN(JY IN NATURE. 
23 
by tlie most advanced .scientitic workers, which show that certain 
birds have acquired a more advanced phimage there than elsewhere, 
and this advancement is proportionally less as we recede from the 
most active area, and as all the teachings of morphology demonstrate 
that characteristics peculiar to the immature or juvenile stage of 
life, which become outgrown or lost at maturity, are those their 
more primitive ancestors bore when fully adult, and that in proportion 
as these peculiarities of youth are outgrown is superiority over their 
predecessors proclaimed. 
-r 
-y— — ^ 
( ' f 
. ■■ „ -- 
m 
\ X 
' ► 6 J 
r *' 
Fig. 8. — Geographical distribution of the true Jays {Garru/us} showing their Euro-Asiatic 
range and the striking coincidence of their paths of dispersal with those of other organisms (after 
Dr. A. Russel Wallace). The inhabited regions are shown in Red and the relative degrees of 
dominance of the various races indicated by paler shades of colouring. 
The Coal Tit, in most parts of Britain, and still more strikingly in 
(jermany, has, according to Mr. Ogilvie (Irant, attained a plumage 
beyond that in which the fully-grown birds in certain parts of Ireland 
and North Africa are still clothed, the North African birds representing 
a more primitive or youthful stage than the Irish race, which have 
advanced a step beyond ; this adult feathering of the African and 
Irish birds being that of the juvenile or nestling stage of the 
British and German race, shows that the African and Irish birds 
retain in mature life the plumage that the British and (xerman birds 
have progressed beyond. 
Amongst other genera, according to Dr. Hartert, showing this 
evolutionary advance are the shrikes, some of the more primitive 
forms of which group, as Lanins excuhitor mollis Eversm., which 
breeds in the northernmost parts of Eastern Siberia, from Kam- 
tschatka to the Lower Yenissei river and Ldnlus cxcubitor horealis 
Vieill., inhabiting North America, both retain in adult life the wavy 
barred hrea.-^ts, which in the European form is a feature of the 
nestling or juvenile plumage only, and is lost in adult life ; whde 
