100 PROC. COTTESWOLD CLUB vol. xiii. (2) 



Now if acquired characters are transmitted, what maybe 

 called the human ability to straighten the hand should dis- 

 place the inherited monkey attitude earlier in those children 

 whose forbears have for several generations been engaged 

 in work which would favour the human finger-extension. 

 That is to say, that the ability to straighten might be ex- 

 pected to appear earlier in certain classes than in others. 

 There is an interesting field here for the collection of 

 accurate data. 



Something else may be noted. Injury and unfavourable 

 environment often cause the re-appearance of ancestral 

 characters. This is very noticeable among fossil molluscs. 

 Now in the human hand injury from an accident increases 

 the bough-grasping tendency, or brings it back, so that no 

 straightening of the fingers is possible. Cold, too, in- 

 creases it, decreasing the ability to straighten. 



The longer an arboreal life was maintained, and the 

 more an animal became adapted thereto, the greater must 

 be the tendency to lose the ability of digit movement in 

 the hands and to lose the power of accurate arm move- 

 ment, — because the fore-limbs must do the greatest share 

 in weight sustaining. On the contrary, the toes of the 

 feet might become the more flexible and delicate instru- 

 ments. There are some interesting facts in this connexion 

 in young children — they have the ability to move the toes 

 separately (see fig. 6), but they are clumsy with the 

 fingers, and the movements of the arm are very awkward. 

 Trying to put something into its mouth the child will 

 probably hit itself in the eye, and then turn the head to 

 the hand instead of bringing the hand to the mouth. 



In bipedal progression the functions of fore and hind 

 limbs are just reversed to what they would be among 

 arboreal quadrumana. The hind limbs are the weight- 

 carriers and the front limbs manipulators. And so pre- 

 viously inherited traits have to be dispensed with, and 



