184 



THE NATURE OF LIMBS. 



The segment supporting these appendages, or first 

 rudiments of the fore-limb in the fish, is the occipital 

 one, or the last vertebra of the skull. The pleurapo- 

 physis of this segment is the seat of all those modifica- 

 tions which have earned for it the special name of 

 "scapula," 51; the hcemapophysis is the seat of those 

 that have led to its being called "coracoid," 52. 



The corresponding segment of the batrachian amphi- 

 uma (Fig. 33) yields the next important modification of 

 these parts. The scapulie, jj^, 51, are detached from the 

 occipnt, or neutral arch; the coracoids, A, 52, are much 

 expanded ; three segments of the diverging appendage, «, 

 are ossified, and two of these segments are bifid, showing 



AJirmuMA. 



PROTEUS. 



the beginning of the radiating multiplication of its parts. 

 The first segment is the seat of those modifications which 

 have obtained for it the special name of "humerus," 53 ; 

 the two divisions of the next segment of the appendage are 

 called "ulna," 53, and "radius," 54; the remainder of the 

 limb is called "manus," or hand; 56 is the gHstly carpus, 

 and the two bony divisions are the digits or fingers, 57. 



The segment supporting the hind-limbs retains most 

 of its typical character in the subterranean reptile called 

 the Proteus ; one sees, e. g. in Fig. 34, that the centrum 

 has coalesced with the neurapophyses, ??, and neural 

 spine, ??5, forming the neural arch from which the dia- 



