304 CONCLUSION. [CSap. XV. 



relative, though not actual lapse of time. A number 

 of species, however, keeping in a body might remain for 

 a long period unchanged, whilst within the same period 

 several of these species by migrating into new countries 

 and coming into competition with foreign associates, 

 might become modified ; so that we must not overrate 

 the accuracy of organic change as a measure of time. 



In the future I see open fields for far more important 

 researches. Psychology will be securely based on the 

 foundation already well laid by Mr. Herbert Spencer, 

 that of the necessary acquirement of each mental power 

 and capacity by gradation. Much light will be thrown 

 on the origin of man and his history. 



Authors of the highest eminence seem to be fully 

 satisfied with the view that each species has been 

 independently created. To my mind it accords better 

 with what we know of the laws impressed on matter by 

 the Creator, that the production and extinction of the 

 past and present inhabitants of the world should have 

 been due to secondary causes, like those determining the 

 birth and death of the individual. When I view all 

 beings not as special creations, but as the lineal descend- 

 ants of some few beings which lived long before the first 

 bed of the Cambrian system was deposited, they seem 

 to me to become ennobled. Judging from the past, we 

 may safely infer that not one living species will transmit 

 its unaltered likeness to a distant futurity. And of the 

 species now living very few will transmit progeny of 

 any kind to a far distant futurity; for the manner in 

 which all organic beings are grouped, shows that the 

 greater number of species in each genus, and all the 

 species in many genera, have left no descendants, but 

 have become utterly extinct. We can so far take a 



