Remarks on the Descent of Animals, 143 



Species," a remarkable bird was found in the lilhograpliiG slates of 

 Solenhofen, Bavaria, the head of which was unfortunately crushed 

 beyond recognition. Eecently, however, another specimen has 

 been found in the same formation, at Eichstadt, Bavaria, with a 

 well preserved head. The celebrated comparative anatomist, 

 Owen, of London, described this bird and called it Archaeopteryx. 

 " There is this wonderful peculiarity about this creature, that so 

 far as its feet are known, it has all the characters of a bird, all 

 those peculiarities by which a bird is distinguished from a reptile. 

 Nevertheless, In other respects, it is unlike a bird and like a rep- 

 tile. There is a long series of caudal vertebrae. The wing differs 

 in some very remarkable respects from the structure it presents in 

 a true bird. In a true bird the wing answers to the thumb and 

 two fingers of the hand, the metacarpal bones are pressed together 

 into one mass, and the whole apparatus, except the thumb, is 

 bound up in a sheath of integument, and the edge of the hand 

 carries the principal quill feathers. It is in that way that the 

 bird's wing becomes the instrument of flight. In the archaeop- 

 teryx, the upper arm bone is like that of a bird ; the two forearm 

 bones are more or less like those of a bird, but the fingers are not 

 bound together — they are free, and they are all terminated 

 by strong claws, not like such as are sometimes foutid in birds, 

 but by such as reptiles possess ; so that in the archaeopteryx we 

 have an animal which, to a certain extent, occupies a place mid- 

 way between a bird and a reptile. It is a bird so far as its foot 

 and sundry other parts of its skeleton are concerned ; it is essen- 

 tially and thoroughly a bird, in the fact that it possesses feathers ; 

 but it is much more properly a reptile, in the fact that what rep- 

 resents the hand has separate bones resembling that which termi- 

 nate the fore-limb of a reptile. Moreover, it had a long tail with 

 a fringe of feathers on each side. From this description it is seen 

 that the archaeopteryx is about three-fourths bird and one-fourth 

 reptile." 



Prof. Marsh has found during the last few years very remark- 

 able forms of birds in the Chalk of Kansas. In the Hesperornis, 

 "says Marsh," "we have a large aquatic bird, nearly six feet in 

 length, with a strange combination of characters. The jaws are pro- 



