HYBRIDISM AMONG COCKATOOS. 21 



parent than to the female; (2) the hybrids may be nearer to 

 the female-parent than to the male ; (3) in reciprocal crosses the 

 hybrids in both cases may be nearer to the male-species than 

 to the female-species ; (4) also, it is probable that in some 

 reciprocal crosses the hybrids in both cases may be nearer to 

 the female-species than to the male-species ; (5) in reciprocal 

 crosses the hybrids may be much alike, and nearly inter- 

 mediate between the two parents. 



There appear to be no examples of the hybrids between 

 distinct animal species being- widely different from both 

 parents. 



We already know from Karl Pearson's researches that the 

 co-efficient of correlation in man between male-parent and off- 

 spring tends to be slightly greater in the inheritance of some 

 characters than between female-parent and offspring. For 

 example, in the case of stature the co-efficient for father and 

 son is '396, and for mother and son *302. 



The few examples of hybridism above quoted do perhaps 

 give some slight evidence of the male-parent sometimes exert- 

 ing a certain general prepotent influence on account of sex ; 

 but the influence of sex is doubtless altogether overshadowed 

 by the prepotency of characters which may be regarded 

 as phylogenetic. The very fact that a particular character 

 occurs in a number of species of a genus is evidence that 

 the character has been strongly inherited. In other words, 

 the view is, that in blended inheritance if one parent of a 

 hybrid has the typical character of the genus, and the other 

 parent has a less usual one, then the typical character seen in 

 the majority of the species of the genus would tend to be 

 more strongly inherited in the hybrid than the more peculiar 

 one. 



Possibly, if it is legitimate to surmise at all in the matter, 

 the hybrid Licmetis nasica ($ x Cacatua galerita ? 

 would not differ greatly from the hybrid above described, 

 since the characters ^appertaining to the large genus Cacatua, 

 to which galerita belongs, might be expected to conceal any 

 small prepotent influence that the male sex might possess. 



