A Still Progressive Tissue. 135 



mammals, the types of which are even more clearly seen 

 to be permanent and unprogressive. 



Cataclysmic changes of the earth's surface, giving rise 

 to new geodetic, climatic, and atmospheric conditions, 

 might, indeed, if not too suddenly destructive, compel 

 certain skeletal alterations and changes of form, both in 

 man and other mammals, although there is the greater 

 probability that such catastrophism would prove fatal to 

 all well-established types of life ; in brief, that the genus 

 homo, or the genus Jos, would perish off the earth sooner 

 than develop into anything else. 



There is little likelihood, however, that further evolu- 

 tion will be fostered by such means, the earth itself having 

 reached an age and a permanence of planetary type, so to 

 speak, when surface mutations of such revolutionary char- 

 acter are not to be looked for. The very permanence of his 

 terrestrial habitat, in fact, is against the further evolution 

 of the human organism, or the development of anything 

 superior in the way of organic apparatus from such causes. 



The widest view of this subject of organism and evolu- 

 tion which we can take is so conclusive to this effect that 

 the theory of a higher type of being than man, hereafter 

 to come from terrestrial evolution, has been practically 

 abandoned, even although it is apparent and can be 

 shown on good evidence that man in his mind, his intellect, 

 and his brain is still progressive and manifestly capable of 

 much future progress. 



