LIFE AND BEHAVIOE OF THE CUCKOO 
187 
CUCULUS CAXORUS COCCYGUS ERYTHROPHTH AI.MUS 
14. Young at Birth: Blind, without Blind, and dry with black skin sprink- 
trace of feathers (v. 20, Sect. 3) ; legs led with white rudimentarj'^ down 
large and strong; restless; some- (feather-tubes) ; legs very large and 
times responds to contact-stimulus, strong; able to raise itself when 
by throwing itself backwards, and holding to twig, and support its 
in this way ejects nest -mates; re- weight with single toe; grasping 
sponse awakened from 1st to 3d reflex very marked. 
day, and lasts about a week. 
15. Quill Stage: reached at one week The same, when it shows fear, 
old; instinct of fear probably longer 
deferred. 
16. Preening or Covihing Instinct: Appears at about beginning of 7th 
probably present, but without the day: feather-tubes "combed" off 
effect shown in the American spe- entire, over large part of body, and 
cies. in a few hours. 
17. Age at Leaving Nest: 21-24 days, 7-8 days, or about 2 weeks before 
when ready for flight. flight. 
18. Climbing Stage: None. Begins upon leaving nost and lasts 
about a fortnight. 
19. Age at flight: About 21-24 daj^s. The same, or longer. 
The facts tabulated in the preceding paragraphs show very 
clearly that while the European and American cuckoos agree in 
the broad outlines of their behavior, and even closely at certain 
points, they diverge widely at others, and chiefly in the following 
respects: (a) The cuckoos of Europe have lost the nest-build- 
ing and brooding practices, and such parental instincts as they 
have retained have become directed mainly to the care of the 
eggs under peculiar conditions; (b) new instincts have arisen 
through modification of the old, or the passage of the old into new 
channels; (c) The eggs have become reduced in size, highly 
variable in color, and have acquired harder shells; (d) the 
young have correlatively lost certain former instincts, have be- 
come modified in respect to others, or have acquired new ones, 
the most striking of which is the evicting instinct,^' as it may 
be called by means of which they get rid of their nest-mates. 
There has probably been a retardation of the rise of fear in the 
young, in consequence of which it has been enabled to remain 
longer in the nest of a nurse, but experimental evidence here is 
defective. 
