102 THE BEAUTIES OF NATURE CHAP. 
verbal description, however, can do justice to 
the marvellous complexity of animal structure, 
which the microscope alone, and even that but 
faintly, can enable us to realise. 
LENGTH OF LIFE 
How little we yet know of the life-history 
of Animals is illustrated by the vagueness of 
our information as to the age to which they 
live. Professor Lankester’* tells us that “ the 
paucity and uncertainty of observations on 
this class of facts is extreme.” The Rabbit is 
said to reach 10 years, the Dog and Sheep 10 
—12, the Pig 20, the Horse 30, the Camel 100, 
the Elephant 200, the Greenland Whale 400 
(?): among Birds, the Parrot to attain 100 
years, the Raven even more. The Atur Par- 
rot mentioned by Humboldt, talked, but could 
not be understood, because it spoke in the 
language of an extinct Indian tribe. It is 
supposed from their rate of growth that among 
1 Lankester, Comparative Longevity. See also Weismann, 
Duration of Life. 
a —— _ — 
_— eo) ae oe eT oe 
aitees 
APT oy eh ge wtp 
