MAN DESCENDED FROM EXTINCT FORMS. 25 



whether extinct or extant, are descended from a common 

 ancestral form, so does the comparative study of the dead 

 and living Indo-Germanic language absolutely convince 

 us that all these languages have sprung from a common 

 origin. This monophyletic view is unanimously adopted by 

 all linguists of importance who have studied the question, 

 and who are capable of passing a critical judgment upon it. 130 

 The point, however, to which I would specially call your 

 attention in this comparison between the various branches, 

 on the one hand, of the Indo-Germanic language, and, on the 

 other, of the vertebrate tribe, is that the direct descendants 

 must never be confounded with the collateral lines, nor the 

 extinct with the extant forms. This mistake is often 

 made, and results in the formation of erroneous notions of 

 which our opponents often take advantage in order to 

 oppose the whole theory of descent. When, for instance, it 

 is said that human beings are descended from Apes, the 

 latter from Semi-apes, and the Semi-apes from Pouched 

 Animals (Marsupialia), very many people think only of the 

 familiar living species of these different mammalian orders, 

 such as are to be found stuffed in our museums. Now, our 

 opponents attribute this erroneous view to us, and, with 

 more craft than judgment, declare the thing impossible ; or 

 else they ask us as a physiological experiment to transform 

 a Kangaroo into a Semi-ape, this into a Gorilla, and the 

 Gorilla into a Man. Their demand is as childish as the 

 conception on which it is founded is erroneous- for all 

 these extant forms have varied more or less from their 

 common parent-form, and none of them are capable of pro- 

 ducing the same divergent posterity which were really 

 produced thousands of years ago by that parent-form. 131 



