APPENDIX 429 



pass from species to species ; the last compared with the 

 first shows scarcely any resemblance, but the intermediate 

 forms connect them completely. Thus we pass from Papilio 

 Podalirius to P. machaon, thence to the species of Vanessa, 

 of Hipparchia, of Apatura, and so on, and finally we recognise 

 the indirect connection of all the species. 



But the matter may be made much clearer by another 

 example. I am able to demonstrate that dogs and cats are 

 indirectly related. The evolution of the carnivora proceeds 

 from the civet cat. The markings of this form lead to those 

 of the cats, of the hyenas, and of the dogs, and if you look at 

 any dog which approximates to the original form of the 

 Canidae, that is, which has the jackal or wolf form, you can 

 discern in very faint dark marks on its skin the stripes of the 

 hyena, and certain corresponding markings of the domestic 

 cat. Even the most conspicuous variations of the markings 

 of the dog which have gradually been produced, the spots 

 of the most varied kinds which are apparently irregularly 

 scattered over the body, can be traced back to these original 

 lines. Again we have always original darker areas which 

 extend over a larger area, then vary in different ways, divide 

 into separate portions, coalesce, and so on, and thus produce 

 markings between which it is apparently impossible to trace 

 any connection. I notice, for instance, that the markings of 

 hunting and sporting dogs can be traced to a simple plan : 

 you find in most cases a spot on the hindquarters, two on 

 the back, one spot on the neck, and again another on the 

 head. 



These examples must suffice for the present occasion. I 

 have next to point out that the males always are the first to 

 assume new characters. To this law I have given the name 

 of " male preponderance." The males then are always at a 

 more advanced stage of evolution than the females. But 

 there is at the same time a difference depending on age, for 



