HI LECTURES ON EVOLUTION 101 



many vertebrae. The structure of the wing differs 

 in some very remarkable respects from that which 

 it presents in a true bird. In the latter, the end 

 of the wing answers to the thumb and two fingers 

 of my hand ; but the metacarpal bones, or those 

 which answer to the bones of the fingers which lie 

 in the palm of the hand, are fused together into 

 one mass ; and the whole apparatus, except 

 the last joints of the thumb, is bound up in 

 a sheath of integument, while the edge of the 

 hand carries the principal quill-feathers. In the 

 Archceopteryx, the upper-arm bone is like that of 

 a bird ; and the two bones of the forearm are 

 more or less like those of a bird, but the fingers 

 are not bound together they are free. What their 

 number may have been is uncertain ; but several, 

 if not all, of them were terminated by strong curved 

 claws, not like such as are sometimes found in 

 birds, but such as reptiles possess ; so that, in 

 the Archceopteryx, we have an animal which, 

 to a certain extent, occupies a midway place 

 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 essentially and 

 thoroughly a bird by its feathers ; but it is much 

 more properly a reptile in the fact that the 

 region which represents the hand has separate 

 bones, with claws resembling those which ter- 

 minate the fore-limb of a reptile. Moreover, it 

 had a long reptile-like tail with a fringe of 

 feathers on each side ; while, in all true birds 



