by the remains of two remarkable skeletons, belonging to that 

 very wonderful reptile-like bird, Archaeopteryx. 



Only two skeletons of this wonderful bird are known, and 

 they were obtained, many years ago, from the Solenhofen, or 

 Lithographic slates of Bavaria. The wing and tail feathers 

 are as perfectly developed as in modern birds. But these 

 precious fossils present two characters which have long since 

 been lost by birds. The first of these is the presence of well- 

 developed teeth in the jaws. The birds of to-day have horny 

 beaks. The teeth bespeak the reptile. The second is the 

 long, tapering tail, which is composed of a series of cylindrical 

 bones, forming a lizard-like appendage. But each bone, be 

 it noted, supported a pair of stiff tail-quills, so that the tail 

 of this ancient bird, in its general appearance, differs in a 

 very striking way from that of a modern bird, wherein these 

 feathers seem all to spring from a common base, fan-wise. 

 But as a matter of fact this appearance is deceptive, for the 

 large bone, or " pygostyle " which supports the tail feathers 

 of the adult, is found, in the embryo, to be made up of a 

 series of separate pieces, agreeing in number with those of 

 the tail of the fossil ancestor, Archaeopteryx. Each of these 

 separate bones has, in fact, in the course of the ages, been 

 shortened up to the condition of mere discs ; and this " tele- 

 scoping " of the vertebrae has brought, the once separated 

 feathers close up, so that their bases lie packed in like the 



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