2-]^ RELICS OF PRIMEVAL LIFE 



seas, and to study Eozoon and its contemporary 

 Protozoa when alive, it is plain that we could not 

 have foreseen or predicted from the consideration 

 of such organisms the future development of life. 

 No amount of study of the prototypal Foraminifer 

 could have led us distinctly to the conception of 

 even a Sponge or a Polyp, much less of any of the 

 higher animals. Why is this? The answer is that 

 the improvement into such higher types does not 

 take place by any change of the elementary sar- 

 code, either in those chemical, mechanical, or vital 

 properties which we can study, but in the adding 

 to it of new structures. In the Sponge, which is 

 perhaps the nearest type of all, we have the mov- 

 able pulsating cilium and true animal cellular 

 tissue, and along with this the spicular or fibrous 

 skeleton, these structures leading to an entire change 

 in the mode of life and subsistence. In the higher 

 types of animals it is the same. Even in the 

 highest we have white blood-corpuscles and ger- 

 minal matter, which, in so far as we know, carry 

 on no higher functions of life than those of an 

 Amoeba ; but they are now made subordinate to 

 other kinds of tissue, of great variety and com- 

 plexity, which never have been observed to arise 



