THE SUTURES. 153 



adult life. This necessity of subdivision into many pieces, does 

 not depend so much on the size, as on the shape of the head. 

 For we find the largest animal, as the elephant, having no 

 more sutures than the smallest, as the mouse. This opinion is 

 also sustained by what we see in other bones. Bones of a 

 very simple shape, as those of the tarsus and carpus, consist 

 from the very beginning of but one piece. But where the 

 shape of a bone is complicated, we find it, while growing, 

 submitted to the same law as the head at large, and consisting 

 of many pieces. In such cases these pieces are united by a 

 species of suture corresponding precisely with the form of su- 

 ture observed between some of the bones of the cranium; as, 

 for example, between the occipital and the sphenoid. Thus, 

 the os femoris, till adult age, consists of five pieces: its two ar- 

 ticular extremities, its body, its trochanter major, and its tro- 

 chanter minor. The cranium itself, before birth, and for some 

 time after, has several of its individual bones consisting each 

 of two or more pieces, which favours still more the idea. 



Some persons think that the sutures of the adult are only re- 

 mains of an arrangement intended exclusively for the benefitof 

 the partarient state, by maintaining a plasticity of the head of 

 the foetus, which admits of its diameters accommodating them- 

 selves to the diameters of the pelvis of the mother. This the- 

 ory is rather too exclusive, though it may be admitted that the 

 sutures in a foetal head have that use, and are in some cases of 

 parturition a most fortunate coincidence, by which the lives of 

 both parties are saved. But it should be observed that in a 

 great number of cases, the head of the foetus never changes its 

 form in passing through the pelvis, because the passage is quite 

 large enough without it; and, again, if the sutures were intend- 

 ed expressly for the parturient state, we ought not to find them 

 in birds, and in such animals as are hatched, because the ne- 

 cessity for them there does not exist.* 



Upon the whole we may safely conclude, that the sutures of 

 the cranium and face are simply a provision for the growing 

 state, and that, like all other provisions for this state, it also 

 ceases at its appropriate period, and sometimes leaves not a ves- 



* A gentleman whose anatomical writings have some vogue in this country, 

 has cut the Gordian knot, by telling us that they are " accidental merely, and of 

 little use!! "Anat. of the Human Body, by John Bell, Surgeon, Edinburgh. 



