160 EVOLUTION 



possibly survive, and as, consequently, there 



is frequently r^nirring Ffam^Hp for 



it lOilo'W'S ^-- L ~Jf ? "ti V fl T- 



rofiable 



ijjirjpr ffafi .fflyrnplfsr find snrflpf]*rr]PS 

 ftniir||tj{yns qf jlfp. _will have a. |}f"tter chance 

 of siiryj^yjiig. and t|jys_be.^^t.urallY. selected. 

 From the strong principle of inheritance 

 sp.]fi(*.t.ef| variety wil 



6 f ny 

 ' n 



There are here three main propositions: 

 (1) Variability is a. fn.p.t. of ]]fft. Variations 



are of frequent occurrence, ar^d some of them 



are, 



(2) Living creatur^ r s ^ : re_very prolific^ 



There is a ceaseless 



struggle for existence and the web of inter- 



relations is SUch that 



rn^.y 



(3) If variations occur in the direction of 

 increased fitness,_if the variations are jtrans- 

 yisj;ThT(R! and if there is.discriminate ^sel^r^gp 

 with reference to these variations, then the 

 ossessors of 



with linger life and^arger 



~ 



families ^yit|] snryival, in shortT If this~is 

 kept up consistently, then new adaptations 

 and, probably with the help of some form of 

 isolation, ^WL^gecieg,, yy^ll jaia^e. 

 THE CASE FOR NATURAL SELECTION. The 



