92 THE ZOOLOGIST. 



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being is placed under unfavourable conditions by the Creator, 

 and roundly charge his whole theory with atheism. One of his 

 supporters, Prof. Asa Gray, quaintly asks : " Are not many in- 

 dividuals and some races of men placed by the Creator under 

 unfavourable circumstances, at least under such as might be 

 advantageously modified ?" 



[Thus Sphex (a hymenopterous insect like a wasp) stings 

 caterpillars and spiders through the nervous system, so that 

 they continue to live and afford food for its larvae in their cells. 

 Another hymenopterous insect, Polynema, deposits its eggs in 

 those of a dragonfly (Agrion virgo), and these are developed at 

 the expense of the latter, which serves as a store of food-yolk. 

 Such instances sufficiently illustrate the unfortunate conditions 

 of certain types under natural conditions, and the same is seen 

 in the white pigs of Virginia, which are poisoned by the paint- 

 root (Lachnanthes) , whilst black pigs escape. 



Again, conscientious adherents of the Church, such as George 

 Henslow, have striven to show that the very same laws of Evolu- 

 tion equally regulate the growth of Keligion, whether in the 

 Individual, the Church, or the Nation. Wasmann, in Germany, 

 adopts similar views as to the evolution of animals, but he 

 excepts man, who has an immortal soul, and has a totally diffe- 

 rent origin from them.] 



Darwin believes that this law of Natural Selection, for in- 

 stance, keeps the colour of certain birds, when once acquired, 

 true and constant ; for if any one was produced with a colour 

 different, say, from the usual hue of a Grouse, hawks would very 

 easily observe it. A white Pigeon in a flock of blue Kocks has a 

 greater chance of being struck by a hawk, and a white wild 

 rabbit is perhaps a conspicuous lure for a fox. 



Natural Selection always acts slowly, and its action depends 

 on the occurrence in nature of certain places which can be better 

 filled through some of the inhabitants of the country undergoing 

 modification of one kind or other. The favoured races super- 

 sede those which are not modified, just as we see breeds of cattle 

 and sheep and varieties of flowers taking the places of older and 

 inferior kinds. 



[Yet in this connection nothing is more remarkable than the 

 persistence of the food-fishes in the ocean. For ages they have 



