26 THE PRESENT CONDITION 



question, too, is not uncertain or doubtful. It is now 

 proved that every plant begins its existence under the 

 same form ; that is to say, in that of a cell — a particle 

 of nitrogenous matter having substantially the same 

 conditions. So that if you trace back the oak to its first 

 germ, or a man, or a horse, or lobster, or oyster, or any 

 other animal you choose to name, you shall find each 

 and all of these commencing their existence in forms 

 essentially similar to each other : and, furthermore, 

 that the first processes of growth, and many of the 

 subsequent modifications, are essentially the same in 

 principle in almost all. 



In conclusion, let me, in a few words, recapitulate 

 the positions which I have laid down. And you must 

 understand that I have not been talking mere theory; 

 I have been speaking of matters which are as plainly 

 demonstrable as the commonest propositions of Euclid — 

 of facts that must form the basis of all speculations 

 and beliefs in Biological science. We have gradually 

 traced down all organic forms, or, in other words, we 

 have analyzed the present condition of animated nature, 

 until we found that each species took its origin in a 

 form similar to that under which all the others com- 

 menced their existence. We have found the whole 

 of the vast array of living forms with which we are 

 surrounded, constantly growing, increasing, decaying, 

 and disappearing ; the animal constantly attracting, 

 modifying, and applying to its sustenance the matter 

 of the vegetable kingdom, which derived its support 

 from the absorption and conversion of inorganic matter. 

 And so constant and universal is this absorption, waste, 

 and reproduction, that it may be said with perfect 



