34 POPULAR ILLUSTRATIONS OF 



that apparently inanimate speck of jelly, and presently you will 

 observe that it has motion. If your observation, however, happen 

 to be interrupted for ever so short a time, you will be surprised that 

 you see this thing no more. There is something there, indeed ; but, 

 instead of appearing like Fig. 31, it has assumed a shape perhaps 

 like that shown in Fig. 32 ; and while you fix your excited attention 

 upon this, it will alter before your eyes to the semblance of Fig. 33 ; 

 and again, ere you can express your wonder (if this is your first 

 sight), it will have changed to something like Fig. 34, and, with 

 equal rapidity, to a form like Fig. 35. Now, if you look for an 

 hour you will probably not see it assume the same figure again. It 

 is always changing, and hence has received the name of the Protean 

 animalcule. It is the Amoeba, and one of the typical forms of the 

 Ehizopoda thus named because the so-called feet or pseudopodia 

 are pushed out from the body so as to appear something like the 

 roots of plants. 



Fig. 31. Fig. 32. Fig. 33. Fig. 34. Fig. 35. 



Figs. 31-35. Forms assumed by Amoeba under the microscope. 



Now, this Amoeba, which I have selected to illustrate the 

 Ehizopoda, has been designed to play a very important part in the 

 physical history of the world, as I shall show by and by. Agassiz, 

 the Owen of the United States, has, in his recently published 

 " Graham Lectures," taken the ground that, although the earlier 

 forms of animal life were created myriads of years before man, they 

 were, notwithstanding, formed with an evident reference to his 

 appearance on earth. I have held the opinion for some years, and 

 I have strong evidence in this direction to give in favour of our 

 little lump of sarcode for it is nothing more. Dr. Carpenter, in 

 his "Introduction to the Study of the Foraminifera," published in 

 1864, by the Bay Society, thus speaks of the Amoeba : " It is a 

 particle of apparently homogeneous jelly, changing itself into a 

 greater variety of form than the fabled Proteus, laying hold of its 

 food without members, swallowing it without a mouth, digesting it 

 without a stomach, appropriating its nutritious material without 

 absorbent vessels or a circulating system, moving from place to place 



