534 



The Journal of Heredity 



boot has had its definite influence (as 

 in limiting the possibiHties of the power 

 of grasp), such generaHzations concern- 

 ing the human foot are very far from 

 true. If Man should wish to point with 

 pride to any organ, the structure of 

 which definitely severs him from all 

 other existing Primates, it is to the foot 

 he should point. If 'missing links' are 

 to be tracked with complete success, 

 the foot, far more than the skull, or the 

 teeth, or the shins, will mark them as 

 Monkey or Man. The weakness of 

 Achilles lay in his heel ; the weakness of 

 the arboreal Primate masquerading as 

 man lies in the structure of its foot." 



To one who is not an anatomist, the 

 most striking difference is in the rela- 

 tive lengths of the toes. In the Gorilla 

 the middle digit on both hand and toot 

 is the longest. The "digital formula" 

 for the foot is exactly the same as for 

 the hand; both may be expressed as: 

 3>4>2>5>1. Such a formula is an 

 exceedingly primitive one, and is found 

 as low in the scale as in water tortoises, 

 at the present day. "The strangely 

 I)rimitive human hand has an identical 

 digital formula, the third being the 

 finger that reaches farthest forwards, 

 the fourth the next, the second the next, 

 followed by the fifth, and the thumb 

 is farthest back of all. There is an al- 

 most equally common variation in the 

 human hand in which the second digit 

 may be as long as, or longer than, the 

 fourth, and this is doubtless due to the 

 functional importance of the index 

 finger. I am not sure that it should 

 not be considered as the typical hu- 

 man condition. In such cases the for- 

 mula stands thus: 3>2>4>5>1, or 

 3>2 = 4>5>1. 



"Man retains a very primitive digital 

 formula for his"^ hand. His nearest 

 Primate kinsfolk retain it for both hands 

 and feet. 



ALTKIiATIONS IN THE FOOT 



"It is when wc attempt to apply 

 this formula to the human foot that 

 we sec how great is the alteration that 

 has taken j^lace between the existing 

 anlhro])oid with the best jirimate foot 

 and Man him.sclf. The digital fonnula 

 for the human foot is as a rule : 1 > 2 > 



3>4>5. vSuch a statement holds good 

 for a majority of the present-day 

 British people. It is commonly as- 

 sumed by artists, and even by surgeons, 

 that the elongated big toe which pro- 

 jects in advance of the other four toes 

 is not a natural human characteristic, 

 but is a result of boot pressure. A 

 long big toe is regarded rather as a 

 deformity than as a natural human 

 possession in which to take justifiable 

 pride. 



"Professor Flower long ago turned 

 his attention to this point, and he 

 examined the feet of hundreds of the 

 barefooted children of Perthshire, and 

 among them all he found no case in 

 which the big toe did not project be- 

 yond the second toe. We must look 

 upon a big toe which dominates the 

 whole series as a typically human and a 

 perfectly natural feature. Neverthe- 

 less, it is common enough to see feet 

 in which the second toe is longer than 

 the big toe. People who have feet with 

 such a digital fonnula are apt to be 

 somewhat proud of the fact, for such 

 a foot is supposed to conform to the 

 'Greek ideal,' but that this type of 

 foot was ever the ideal of the Greek 

 artists is disputed by some authorities 

 on the subject, and certainly we may 

 assume that it is less typically human, 

 and more ape-like, than the type of 

 foot of the average hospital patient who 

 po.ssesses a long big toe." 



"Zoologically speaking, we may say 

 that the very useful and specialized foot 

 adapted for terrestrial progression is a 

 foot of few digits. It may. in fact, be 

 a foot composed of a solitary digit. 

 The evolutionary stages by which the 

 horse has come to stand solely u])on its 

 third digit are well known. Similar 

 processes produced the two digited foot 

 of the deer and of the ostrich. There 

 can be no doubt that Man is trusting, 

 not to his third digit, but to his first, 

 and that all the others are undergoing a 

 process of comparative atrophy. This 

 is in rcalit.y a most interesting prob- 

 lem. There is an admitted tendency 

 to six^cializc one digit in a thoroughly 

 ada])te(1 terrestrial foot. Man ap])lie(l 

 an arboreal foot to terrestrial ])ro- 

 gression, and in this arboreal foot the 



