706 THE DESCENT OF MAN 



more especially from the fawns of so many species being 

 spotted, we may conclude tliat the now living members of 

 the deer family are the descendants of some ancient species 

 wbich, like the axis deer, was spotted at all ages and sea- 

 sons. A still more ancient progenitor probably somewhat 

 resembled the Hyomoschus aquaticus — ^for this animal is 

 spotted, and the hornless males have large exserted canine 

 teeth, of which some few true deer still retain rudiments. 

 Hyomoschus, also, offers one of those interesting cases of 

 a form linking together two groups, for it is intermediate 

 in certain osteological characters between the pachyderms 

 and ruminants, which were formerly thought to be quite 

 distinct." 



A curious difficulty here arises. If we admit that col- 

 ored spots and stripes were first acquired as ornaments, 

 how comes it that so many existing deer, the descendants 

 of an aboriginally spotted animal, and all the species of 

 pigs and tapirs, the descendants of an aboriginally striped 

 animal, have lost in their adult state their former orna- 

 ments? I cannot satisfactorily answer this question. We 

 may feel almost sure that the spots and stripes disappeared at 

 or near maturity in the progenitors of our existing species, so 

 that they were still retained by the young; and, owing to the 

 law of inheritance at corresponding ages, were transmitted 

 to the young of all succeeding generations. It may have 

 been a great advantage to the lion and puma, from the open 

 nature of their usual haunts, to have lost their stripes, and 

 to have been thas rendered less conspicuous to their prey; 

 and if the successive variations by which this end was gained 

 occurred rather late in life, the young would have retained 

 their stripes, as is now the case. As to deer, pigs, and 

 tapirs, Fritz Miiller has suggested to me that these ani- 

 mals, by the removal of their spots or stripes through 

 natural selection, would have been less easily seen by 



*'' Falconer and Cautley, "Proc. Geolog. Soc," 1843; and Falconer's 

 "Pal. Memoirs," vol. '. p. 196. 



