Chap. XIII. EEVEllblON. 35 



parts now in a more or less rudiment a r^^ condition, — the re- 

 appearance of organs of which not a vestige can be detected, 

 — and to these may be added, in the case of animals, the 

 presence during youth, and subsequent disappearance, of cer- 

 tain characters which occasionally are retained throughout 

 life. Some naturalists look at all such abnormal structures as 

 a return to the ideal state of the group to which the affected 

 beins: belong-s ; but it is difficult to conceive what is meant to 

 be conveyed by this expression. Other naturalists maintain, 

 with greater probability and distinctness of view, that the 

 common bond of connection between the several foregoing 

 cases is an actual, though partial, return to the structure of 

 the ancient progenitor of the group. If this view be correct, 

 we must believe that a vast number of characters, capable of 

 evolution, lie hidden in every organic being. But it would 

 be a mistake to suppose that the number is equally great in 

 all beings. We know, for instance, that plants of many 

 orders occasionall}^ become peloric ; but many more cases have 

 been observed in the Labiatse and Scrophulariaceee than in 

 any other order ; and in one genus of the Scrophulariaceae, 

 namely Linaria, no less than thirteen species have been de- 

 scribed in this condition.'^ On this view of the nature of 

 peloric flowers, and bearing in mind certain monstrosities in 

 the animal kingdom, Ave must conclude that the progenitors of 

 most plants and animals have left an impression, capable of 

 redevelopment, on the germs of their descendants, although 

 these have since been profoundly modified. 



The fertilised germ of one of the higher animals, subjected 

 as it is to so vast a series of changes from the germinal cell to 

 old age, — incessantly agitated by what Quatrefages well calls 

 the toiirhillon vital, — is perhaps the most wonderful object in 

 nature. It is probable that hardly a change of any kind 

 affects either parent, without some mark being left on the 

 germ. But on the doctrine of reversion, as given in this 

 chapter, the germ becomes a far more marvellous object, for, 

 besides the visible changes which it undergoes, we must 



" Moquin-Tandon, ' Teratologie,' p. 186. 



