20 L. W. SACKETT 



Gould (15) explains the whole problem upon a different 

 basis: "All that is needed to explain the righthandedness of 

 94% of the children is some ancestral savage custom, habit, or 

 necessity widely prevalent which inclined to the use of the right 

 hand and eye for one or two exceptionally intellectual tasks. 

 The inheritance of aptitude, the force of custom and the necessity 

 of the struggle for existence would certainly fix the persistence 

 of the peculiar excellence." The same author also proposes 

 another explanation: "physiologically, therefore, the reason 

 why an infant puts forth the right hand to grasp objects is 

 because the right eye is the one which is nearest perfect visually, 

 anatomically or optically. The law derived from the phylum 

 of the entire past is that the right eye and the right forefoot, 

 or right hand, must work together * * * Handedness, if 

 one may devise a word, becomes either righthandedness or left- 

 handedness, according to the dictating condition of the better 

 eyedness, right or left." In spite of Baldwin's assurance that 

 it is impossible and Gould's dogmatic assertion that it is non- 

 sense that animals are right footed or leftfooted because the 

 differentiation "could only arise with sign language and count- 

 ing, and animals do not make gestures or count," Mollison (28) 

 has demonstrated that all the primates at birth show charac- 

 teristic anatomical differences in the fore limbs which corres- 

 pond remarkably with the asymmetry of the species. 



Porcupines have very little, if any tendency to be either right- 

 handed or lefthanded, as shown in the facts given below that 

 habits in the use of the hand when once formed could be broken 

 in a few days with few traces of the old habit remaining, and to 

 return to one of them was a task sometimes greater than first 

 forming or breaking the habit. But the reason why they re- 

 sponded symmetrically with the experimenter is not to be 

 explained upon a physiological basis. If it were due to sug- 

 gestion from the operator it was not only unconscious but 

 contrary to the conscious efforts to prevent any such cue. If 

 there was such an influence it was sufficiently general to per- 

 mit of change of experimenters in the midst of the learning 

 process in 10 different animals without disturbing the learning 

 curve. This was exactly the case with the well-known horse 

 "Hans" as well as with Haggerty's dog, but still it seems hardly 

 reasonable when one considers what slight changes in condition 



