THE ZOOLOGIST 



No. 770.— August 1905. 



BIOLOGICAL SUGGESTIONS. 



EXTEEMINATION IN ANIMAL LIFE. 



Part I. — By Natukal or non-Human Agency. 



By W. L. Distant. 



We need not marvel at extinction ; if we must marvel, let it be at our 

 own presumption in imagining for a moment that we understand the many 

 complex contingencies on which the existence of each species depends. — 

 Chas. Darwin. 



There is no species of animal which is not exposed to destruction through 

 various accidental agencies— by hunger or cold, by drought or flood, by 

 epidemics or enemies, whether beasts of prey or parasites. — A. Weismann. 



To me the greatest marvel is the countless, the infinite number of the 

 organisms that have existed, each with its senses and feelings, whose bodies 

 now help to build up the solid crust of the earth. — Eich. Jefferies. 



" Imperfection of the Geological Record " is a phrase that 

 justly accounts for many of those lacunse which disfigure, but do 

 not impair, the evidential structure on which rests the conception 

 of animal evolution. To realize how many links must be missing 

 from the palasontological cable which moors the present fauna 

 of this planet with the life existing in the ages of the past, we 

 have only to study and enumerate the frequent dislocations 

 which occur in our own time to the chain of life. Extinction 

 and extermination are terms which zoologists are too often com- 

 pelled to use. Hunters no longer seek the Bison on the American 

 Zool. 4tk ser. vol. IX., August, 1905. z 



