222 LAMARCK, HIS LIFE AND WORK 



tables seem consequent to the other properties of the 

 materials which possess them " {The Loves of the 

 Plants, p. 38, note). 



In his Zoonomia (§ xxxix., vi.) Darwin also speaks 

 of the efficient cause of the various colors of the 

 eggs of birds and of the hair and feathers of animals 

 which are adapted to the purpose of concealment. 

 " Thus the snake, and wild cat, and leopard are so 

 colored as to resemble dark leaves and their light in- 

 terstices " (p. 248). The eggs of hedge-birds are 

 greenish, with dark spots ; those of crows and mag- 

 pies, which are seen from beneath through wicker 

 nests, are white, with dark spots ; and those of larks 

 and partridges are russet or brown, like their nests or 

 situations. He adds : " The final cause of their 

 colors is easily understood, as they serve some pur- 

 pose of the animal, but the efficient cause would seem 

 almost beyond conjecture." Of all this subject of 

 protective mimicry thus sketched out by the older 

 Darwin, we find no hint or trace in any of Lamarck's 

 writings. 



8. Great length of time. He speaks of the "great 

 length of time since the earth began to exist, per- 

 haps millions of ages before the commencement of 

 the history of mankind " (p. 240). 



In this connection it may be observed that Dr. 

 Darwin emphatically opposes the preformation views 

 of Haller and Bonnet in these words ; 



" Many ingenious philosophers have found so great 

 difficulty in conceiving the manner of the reproduc- 

 tion of animals that they have supposed all the 

 numerous progeny to have existed in miniature in 



