PEDIGREE. 665 



Pedigree. Birds have many structural affinities with 

 Reptiles ; some of the ancient Dinosaurs present approxi- 

 mations to Birds ; the extinct flying Pterodactyls show that 

 it was possible for flight to be developed among Reptiles ; 

 the oldest bird Arch&opteryx- -v$> in many ways a 

 connecting link between the two classes ; and the develop- 

 ment of some Birds reveals many remarkable resemblances 

 with that of Reptiles, therefore, with the strength of the 

 general argument for evolution to corroborate us, we 

 conclude that birds evolved from a Reptile stock. 



Speaking of his work on the development of the fowl, 

 W. K. Parker wrote in 1868: "Whilst at work I seemed 

 to myself to have been endeavouring to decipher a 

 palimpsest, and one not erased and written upon again 

 just once, but five or six times over. Having erased, as it 

 were, the characters of the culminating type those of the 

 gaudy Indian bird I seemed to be amongst the sombre 

 Grouse ; and then, towards incubation, the characters of the 

 Sandgrouse and Hemipod stood out before me. Rubbing 

 these away, in my downward work the form of the Tinamou 

 looked me in the face ; then the aberrant Ostrich seemed 

 to be described in large archaic characters ; a little while, 

 and these faded into what could just be read off as 

 pertaining to the Sea Turtle ; whilst underlying the whole, 

 the Fish, in its simplest Myxinoid form, could be traced in 

 morphological hieroglyphics." 



More than twenty years later, the same accomplished 

 embryologist described the development of the " Reptilian 

 Bird" -Opisthocomus cristatus. In this form the unhatched 

 chick has a paw-like hand, three clawed fingers and a 

 rudiment of a fourth, a wrist of numerous carpal elements, 

 and many other features suggestive of reptilian descent. 

 It is not surprising, then, that to Parker a bird seemed 

 as " a transformed and, one might even say, a glorified 

 Reptile." 



It is likely, then, that Birds arose from an ancient Saurian 

 stock, but by what steps and under what impulses we do 

 not know. To some it seems enough to say that the 

 evolution was accomplished gradually in the course of 

 natural selection by the fostering of fit variations and the 

 elimination of the disadvantageous ; to others it seems that 



