29* STUDIES IN THE EVOLUTION OF ANIMALS 



We may be on the eve of momentous revelations concerning 

 not only the appearance of monstrous forms among human beings 

 and domestic animals, but also concerning the sudden appearance 

 of new types of animals in geological periods on monstrous lines \ 

 These artificial ways of evolving monstrosities may yet be able to 

 teach us how the long tail of the Archeopteryx may have been 

 reduced in one generation to the short tail of the modern bird, or 

 vice versa ; how the long tail of one kind of Monkey may have been 

 reduced in one generation to the stump of other kinds, and to the 

 diminutive tail of Man ; how the many digits of the Ichthyosaur 

 may have been suddenly reduced to the five digits of the Plesiosaur, 

 or of some other ancestor of the numerous tribe of five-digited 

 animals. 



'We must not forget/ says Agassiz, 1 'that we are the lofty 

 children of a race whose lowest forms lie prostrate within the 

 water, having no higher aspiration than the desire for food ; and 

 we cannot understand the possible degradation and wretchedness 

 of Man without knowing that his physical nature is rooted in all 

 the material characteristics that belong to his type, and link him 

 even with the Fish.' 



Changes in the cells of the ovum during segmentation, 

 changes after the embryo became differentiated through disturb- 

 ance of the controlling nervous and vascular tissues, might at any 

 time have given rise to what is called a monstrous form, which if 

 unfit would die out, but if fit might endure and transmit its 

 monstrous form. 



It would all depend upon whether the monstrous form could enter 

 into sexual union with the normal forms. In the case of most 

 fishes, however, even this would not be needed, and the facility 

 with which the sperm cell can reach the germ cell in these low 



1 Life and Work, by Dr. Charles F. Holder, p. 189. 



