FOSTER PARENTAGE. 483 



given me by a relative, or other birds sitting on dog- 

 pups. 



And still more remarkable is the occasional suckling of 

 individuals of more than one species at the same time by the 

 same mother, as in the case of a cat that tried to suckle 

 chickens along with her own kittens. 



The most common cause or motive that leads to the 

 adoption of the young of other animals is the loss of a 

 mother's own young, and the felt necessity of gratifying her 

 bereaved maternal instinct. So strong, so urgent, so irresis- 

 tible even, is this necessity, that it leads occasionally to the 

 abduction, or theft, of the young of other animals. No doubt 

 the result is usually beneficent, so far as concerns the up- 

 bringing of the abducted young, seeing that the self-consti- 

 tuted foster-mother lavishes on them all the care she would 

 have bestowed on her own. Nevertheless, there is a selfish 

 disregard of the feelings of the other and true mother, who 

 is bereaved by such an abduction. 



Sterility the want of offspring operates in the same 

 way as bereavement or loss of young. The female of ma- 

 ture age, whose longings for progeny have not been gratified 

 in the natural way, takes the only means that remain to 

 .her of so far satisfying her paramount desire to have some 

 of her own species on whom to lavish her overflowing af- 

 fection. 



This sort of what may be called vicarious maternity, this 

 assumption of the duties of a mother, is not always confined 

 to the female. There are occasional exceptional cases in 

 which the male takes a female's place in the hatching and 

 up-bringing of young, whether its own or those of other 

 species or genera. Thus we are told of a male turkey hatch- 

 ing duck's eggs. 



Generally speaking, the adoption of foster-young is 

 voluntary ; the foster-mother is self-elected. But in some 

 cases the bringing up of the young of other species or genera 

 is involuntary or non-voluntary ; or at least there is no spon- 

 taneous selection, either of the maternal office, or of the 

 objects of affection ; for instance, where young are deserted, 

 orphaned and cast upon the care of sometimes an unwitting 



