THE SKELETON 



89 



progressive element in human development in other words, 

 the greater development of the thumb and the great toe of the 

 male must be considered as a recent acquirement. Accom- 

 panying this difference in the first toe, we note also the 

 slighter reduction of the length of the other toes, and especially 

 of the middle phalanges, in Man, as compared with woman. Man 

 has, as a rule, the original elongated type of toe A 



woman the shortened and compressed type. 

 Further interesting results might be 

 obtained by a careful comparison of the tarso- 

 metatarsal joint of the first toe in the various 

 human races and in the Apes. 



While, thus, progressive development takes 

 place on the inner or tibial side of the foot 

 as the result of functional adaptation, the 

 following retrogressive processes take place 

 on the outer or fibular side : 



The little toe is not infrequently two- 

 jointed, the middle and terminal phalanges 

 being synostotically confluent. Pfitzner found 

 this to be the case in thirteen out of forty- 

 seven examples. This fusion, which is, as a 

 rule, found on both feet, is not due to the 

 pressure of shoes or to any other mechanical 

 causes, 1 but to the fact that the little toe 

 and its metatarsus 2 are in process of degene- 

 ration. This process of reduction, which 

 may end in the little toe becoming in a measure like the thumb 

 and great toe, two-jointed, is particularly interesting, as it is 

 taking place, so to speak, under our eyes. All stages from 

 incomplete to complete fusion can be observed. Further, this 

 degeneration of the little toe apparent in these facts can also 

 be gathered from the condition of its muscles; [of these the 

 flexor brevis often sends either but a very weak offshoot to the 

 little toe, or, like the extensor brevis, none at all.] 



1 I find this synostosis also present in the skeletons of Egyptian mummies of 

 various ages, not excluding children. It may here be remarked that, according to 

 Balz, among the Japanese, who do not wear shoes, the little toe appears quite as 

 reduced as in the European foot. 



2 We are at present unable to deal with the question of the significance of the 

 independent origin of the fifth metatarsal tuberosity, which is the more surprising 

 in consideration of the frequency of retrogressive processes on the fibular side of 

 the foot. 



right hind -limb, of a 



uterine life, to show 



thumb and the great toe 



