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 iy 
—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- 
Fig. 63. 
; ‘ ; 4 A, right fore-limb; B, 
seven examples. This fusion, which is, as a right hind-limb, of a 
: human embryo in the 
aeoounmcdmom both feet, 1s not due to the _. 4d month of intra. 
pressure of shoes or to any other mechanical uterine life, to show 
Pmees ub to the fact that the little toe © {7° “muanty ™ po 
and its metatarsus? are in process of degene- _ thumb and the great toe 
ration. This process of reduction, which Me 
may end in the httle toe becoming in a measure like the thumb 
and great toe, two-jointed, 1s 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. 
