3666 Birds, 



great excitement or alarm), it is said, will produce similar effects on 

 birds." — *■ Familiar History of British Birds,' vol. i. chap. iv. p. 84. 



Now, if Bishop Stanley is correct that birds do change colour from 

 fright, I think I may lay claim to a prima facie case, that the black- 

 bird in question changed colour from that cause ; for that he was 

 excessively terrified by the " crocking," is clearly proved by his sub- 

 sequent and prolonged restlessness, which was so great as to cause 

 fears to be entertained for his life. I have often known caged birds 

 to be very much frightened from a variety of causes, but in no instance 

 before have I seen or heard of the alarm existing for days after the 

 cause of that alarm had passed away. Herein the blackbird shows 

 that he was more than ordinarily terrified ; and I repeat, that if the 

 Bishop's statement be correct, the blackbird in question would have 

 been just the subject in which I should have expected a change of 

 colour to appear. 



Again, it is an undisputed fact that the hair of human beings has 

 in many cases become perfectly white from sudden and extreme 

 fright: not to mention other well-authenticated instances, I myself 

 know more than one such occurrence, wherein the hair has become 

 in a single night entirely bleached from most agonizing terror. Now 

 the analogy existing between the human hair and the feathers of a 

 bird is very great : their manner of growth, their nourishment by 

 means of juices is very similar; and this is more particularly the 

 case with the germs of feathers, which, before the old ones are shed 

 at the time of moulting, are always led into the cavities vacated by 

 the old ones, and w T hich I conceive must be the more easily acted 

 upon by the withdrawal of the fluid containing the colouring mat- 

 ter, than the perfectly formed and therefore more dried and solid 

 feathers can be. This I conceive to be the reason for the change in 

 the plumage of the blackbird taking place, not immediately upon the 

 fright, but at the next moult after it. But, to render my view of it 

 more clear, it will be necessary in the first place to quote, at some 

 length, the whole method of the production of a feather, as described 

 by some of the writers most worthy of attention on this point. 



Malpighi says as follows : — " Birds recently hatched are covered 

 with yellowish hairs, which burst from a follicle, as from a root, in lit- 

 tle bundles of more than twelve, and spread on the surface of the skin. 

 These, if followed by tearing away their sheath, are seen to spring 

 from the top of a very small delicate transparent follicle, containing 

 the rudiment of the feather, which, as it grows, presents the appear- 

 ance of a black sheath beneath the skin. The sheath or membranous 



