14 Bird KILLING IN ORNITHOLOGY. 
the bird killed. They refer in the main, though very vaguely in- 
deed, to previous birds; and are thus of archaeologic importance 
chiefly and of a pertinence to contemporary study as slight as can 
be conceived. But bones themselves are of unequal plasticity 
and (speaking in scale of plasticity) tend into horny parts (bill, 
feet, etc.). These horny features, solely because more plastic and 
thus less valuable than bones as a chronicle of anything previous 
to the moment of death, are a closer approach to pertinence as a 
basis of inference. But are far from a discriminating record of 
the subtle activities of life. Much more can be guessed of a 
bird’s consciously metabolic character or psychologic detail from 
bill and feet than from bones; but this tends by the same causes 
to represent directly if one fact, then not any other; the subtler 
discrimination, because iz ¢he chronicle fixed, barring out the uni- 
versality or continuity of living action. Whereas the bones in the 
main are a fair chronicle not of one’s bird, but of generalities never 
actually contemporaneous with the bones, the bills and feet are less 
fair as any general chronicle and far more restricted as to what 
individuality they chronicle when regarded after death. But here 
arises the new correction that the bill and feet can almost as ac- 
curately be observed in life, where they serve not as a doubtful 
chronicle of limited groups of acts; but in interminable variety as 
features of a metabolic activity. To a keen sense for osteology 
even the bones in action (once their general sort be known) can 
be thus observed readily enough. And, if this be not with perfect 
precision, pray how else are they observed in action at all? But 
the feet and bill in action stare you in the face. Pace for pace as 
the ease of comparative observation in the life increases, decreases 
the value in the corpse for chronicle; as also increases the value 
in the life as metabolic subject-matter for science. Whereas there 
is ostensibly one set of bones through most of a bird’s mature life- 
time (I do not here object to the study of embryology), it begins to 
be evident that bill and feet live and die (i. e. grow and wear out 
and are renewed with differences) many times in a lifetime — the 
feathers more rapidly yet. And whereas the bones may be a tol- 
erable chronicle of many ancestral lives and of the dead hand in 
the present specimen; or again, by minutest microscopy, may 
afford chronicle of some slight metabolism per se, the feathers are 
