260 ROUND THE YEAR 



are absolutely restricted to the class of Birds, and we 

 have no information respecting any extinct feathered 

 animal which was not in essentials a Bird. All 

 known Birds are feathered, just as all known Mammals 

 are hairy. 



I can remember something of the excitement which 

 was roused among naturalists by the discovery in 1 860 

 of a. fossil feather in the lithographic limestone of 

 Solenhofen in Bavaria. That Birds had existed in the 

 remote Jurassic period was a startling announcement, 

 but how tantalising to have no record of the fact 

 beyond a single feather ! The suspense was not long 

 protracted. The very next year the same quarries 

 revealed that fine skeleton of Archaeopteryx which is 

 now in the British Museum, and no doubt was enter- 

 tained that it was this primitive Bird which had yielded 

 the solitary feather found a year earlier. 



Take a Bird (a Sparrow is suitable, but any common 

 Bird will do) with all its feathers on, and notice how 

 they are set upon the body. By plucking half the 

 Bird, you can see that the feathers are not placed 

 at equal distances. They are inserted into definite 

 tracts, with bare spaces between. There is a feather- 

 tract along the spine, and a double feather-tract along 

 the front of the body. The sides are to a great extent 

 bare, more in some Birds than in others. If the whole 

 body were closely feathered, the action of the wings 

 would be impeded. But the flightless Ostriches and 

 Penguins are uniformly feathered. 



Observe the principal quills used for flight (prima- 

 ries), and notice that they are inserted into the 

 hand. A Bird's hand is so reduced and mutilated that 



