292 Zoological Priticiples of Classification^ 



carnivorous ; and, consequently, acquire pretty certain data 

 respecting the probable form of the other bones of the limbs, 

 the nature of the teeth, &c. 



These two laws, as we have stated, regulate the determi- 

 nation of fossil bones ; and the following, according to my 

 view, is the logical process in accordance with it, that we 

 ought to follow in investigations of this kind. 



The first thing to be done is to determine the place of the 

 bone in the skeleton ; that is to say, to determine what name 

 it ought to bear as a bone. This first inquiry, made accord- 

 ing to the law of the unity of organic composition, renders 

 a certain knowledge of osteology necessary, and requires a 

 little practice. It may be facilitated by studying, in the dif- 

 ferent bones of the body, what are the characters which ren- 

 der them most certainly recognisable. Thus we shall soon 

 perceive, for example, that among the bones of the mammi- 

 fera, the femur and humerus are distinguished by this, that 

 one of their articulations has a rounded head ; and that the 

 first diff^ers from the second by having a more distinct neck, 

 and its inferior extremity terminated by two condyles ; while 

 the humerus articulates by a pulley. We shall perceive, in 

 like manner, that the tibia may be known by its two con- 

 dyles, the cubitus by its olecranon, &c. By studying osteology 

 in this point of view, we shall soon become accustomed to 

 distinguish the various bones, and this first part of the de- 

 termination will rarely offer serious difficulties. 



This first point obtained, we will then study the bone with 

 respect to the law of concordance of characters, and insti- 

 tute the comparison which should determine to what family 

 or genus we ought to refer the animal to which this frag- 

 ment belonged. In this investigation, the law I have men- 

 tioned furnishes two different means, which it is of conse- 

 quence to distinguish, in order to form a complete idea of its 

 operation. 



It furnishes, in the first place, rational nieanSj by the 

 rigorous deductions which may be drawn directly from the 

 principle itself. Thus the possession of a large ungueal 

 phalange, flattened below, and nearly in the form of a trian- 

 gular pyramid, will prove, beyond doubt, that the animal to 



