36 THE BOOK OF A NATURALIST 



this animal is our relation, but even such a creature 

 as the bat ! 



Look on this picture, and on this ! On the eyes, 

 for instance, of these two beasts, and we see at 

 once that the bat is an example of extreme degenera- 

 tion ; also that it is the most striking example in 

 the animal world of a degenerate in which the 

 downward process has at length been arrested, and 

 instead of extinction a new, different, and probably 

 infinitely longer life given to it. 



We are reminded of the flea the remote de- 

 scendant, as we deem, of a gilded fly that was 

 once free of the air and feasted at the same sunlit 

 flowery table with bright-winged butterflies and 

 noble wasps and bees. 



There are those who have doubts about this 

 genealogical tree of the bat, and would have it 

 that he is an insectivore related to moles, shrews, 

 and such-like low-down animals, but the main facts 

 all point the other way. And we may assume that 

 the bat our familiar flittermouse, since we are not 

 concerned with the somewhat different frugivorous 

 bats of the tropics is the remote descendant of a 

 small degenerate lemur that inhabited the upper 

 branches of high trees in the African forest ; that 

 he became exclusively insectivorous and developed 

 an extreme activity in capturing his winged prey, 

 and was in fact like the existing small lemur, the 

 golago, which in pursuing insects " seems literally 

 to fly through the air," as Sir H. Johnston has 

 said. Finally, there was the further development, 



