ANCESTORS OF BIRDS. 3 



It is iinncecssarv to discuss here the rehitiuiiships of tlie 

 birdlike re})tile>, luit, as tlie most convincing argument 

 in support of the theory of the re})tiHan descent (jf birds, 

 I present a restoration of the Archaioptervx, the earliest 

 known progenitor of the class Aves. Tliis restoration is 



Fig. 1. — Kestoration of the ArchfEopteryx, a toothed, reptilelike bird of the 

 Jurassic period. , (About 1/5 natural size.) 



based on an examination of previous restorations in con- 

 nection with a study of the excellent plates which have 

 been pul)lished of the fossils themselves.''^ Two s])eci- 

 mens have been discovered ; one being now in the British 

 ^Museum, the other in the Berlin Museum. They were 

 both found in the lithographic slates of Solenhofen, in 

 Bavaria, a formation of the Jurassic period, and, together, 

 furnish the more important details of the structure of this 

 reptilelike bird. 



This restoration, therefore, while doubtless inaccurate 



* For recent papers on the Archa'oitteryx see Natural Science 

 (Macmillan Co.), vols, v-viii. 



