ANCESTORS OF BIRDS. 8 
It is unnecessary to discuss here the relationships of the 
birdlike reptiles, but, as the most convincing argument 
in support of the theory of the reptilian descent of birds, 
I present a restoration of the Archsopteryx, the earliest 
known progenitor of the class Aves. This restoration is 
Fie. 1.—Restoration of the Archwxopteryx, a toothed, reptilelike bird of the 
Jurassic period. (About 1/, natural size.) 
based on an examination of previous restorations in con- 
nection with a study of the excellent plates which have 
been published of the fossils themselves.* Two speci- 
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 Archwopteryx see Natural Science 
(Maemillan Co.), vols. v-viii. 
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