214 MENTAL EVOLUTION IN ANIMALS. 



being prolonged ; for a pea-chick requires sucli care for a 

 very mncli longer time than does an ordinary chick. As the 

 separation between a hen and her chickens always appears to 

 be due to the former driving away the latter when they are 

 old enough to shift for themselves, I scarcely expected the 

 hen in this case to prolong her period of maternal care, and 

 indeed only tried the experiment because I thought that if 

 she did so, the fact would be the best one imaginable to show 

 in what a high degree hereditary instinct may be modified by 

 peculiar individual experiences. The result was very sur- 

 prising. For the enormous period of eighteen montlis this 

 old Brahma hen remained with her ever-growing chicken, 

 and throughout the whole of that time she continued to pay 

 it unremitting attention. She never laid any eggs during 

 this lengthened period of maternal supervision, and if at any 

 time she became accidentally separated from her charge, the 

 distress of both mother and chicken was very great. Even- 

 tually the separation seemed to take place on the side of the 

 peacock ; but it is remarkable that although the mother and 

 chicken eventually separated, they never afterwards forgot 

 each other, as usually appears to be the case with hens and 

 their chickens. So long as they remained together, the 

 abnormal degree of pride which the mother showed in her 

 wonderful chicken was most ludicrous ; but I have no space 

 to enter into details. It may be stated, however, that botii 

 before and after the separation the mother was in the habit 

 of frequently combing out the top-knot of her son — she 

 standing on a seat or other eminence of suitable height, and 

 he bending his head forward with evident satisfaction. This 

 fact is peculiarly noteworthy, because the practice of combing 

 out the top-knot of their chickens is customary among pea- 

 hens. In conclusion, I may observe that the peacock reared 

 ])y this Brahma hen turned out a finer bird in every way than 

 did any of his brothers of the same brood which were reared 

 by their own mother, but that on repeating the experiment 

 next year with another Brahma hen and several pea-chickens, 

 the result was different, for the hen deserted her family at 

 the time when it is natural for ordinary hens to do so, and in 

 consequence all the pea-chickens miserably perished."* 



I allude to the followincp instructive case from Jesse's 



o 



" Gleanings,' 't because it has been independently and uncon- 



* Nature, Oot. 28, 1875. f VoL i, p. 98. 



