SEXUAL SELECTION 705 



Kfe as their parents, and yet are colored in a different man- 

 ner, it may be inferred that they have retained the coloring 

 of some ancient and extinct progenitor. In the family of 

 pigs, and in the tapirs, the young are marked with longi- 

 tudinal stripes, and thus differ from all the existing adult 

 species in these two groups. With many kinds of deer the 

 young are marked with elegant white spots, of which their 

 parents exhibit not a trace. A graduated series can be fol- 

 lowed from the axis deer, both sexes of which at all ages 

 and during ail seasons are beautifully spotted (the male 

 being rather more strongly colored than the female), to 

 species in which neither the old nor the young are spotted. 

 I will specify some of the steps in this series. The Mant- 

 churian deer [Oervus mantchuricus) is spotted during the 

 whole year, but, as I have seen in the Zoological Gardens, 

 the spots are much plainer during the summer, when the 

 general color of the coat is lighter, than during the winter, 

 when the general color is darker and the horns are fully 

 developed. In the hog-deer {Hyelaphus porcinus) the spots 

 are extremely conspicuous during the summer, when the 

 coat is reddish brown, but quite disappear during the win- 

 ter, when the coat is brown.*' In both these species the 

 young are spotted. In the Virginian deer the young are 

 likewise spotted, and about five per cent of the adult 

 animals living in Judge Caton's park, as I am informed 

 by him, temporarily exhibit, at the period when the red 

 summer-coat is being replaced by the bluish winter-coat, 

 a row of spots on each flank, which are always the same in 

 number, though very variable in distinctness. From this 

 condition there is but a very small step to the complete 

 absence of spots in the adults at all seasons; and, lastly, 

 to their absence at all ages and seasons, as occurs with cer- 

 tain species. From the existence of this perfect series, and 



■" Dr. Gray, "Gleanings from the Menagerie of Knowsley," p. 64. Mr. 

 Blylih, In speaking ("Land and Water," 1869, p. 242) of the hog-deer of Cey- 

 lon, says it is more brightly spotted with white than the common hog-deer, at 

 the season when it renews its horns. 



