308 Proofs of Ei'olutlo7i. 



progress, for Evolution always insists on the readjustment 

 of organs to environment. The changes are best for the 

 animal under the circumstances, and therefore truly an 

 advance for him. This tendency to reversion is shown by 

 the stripes on some horses and mules — a survival of the 

 stripes on the wild horse, such as we see on the zebra; 

 also, by the animal teeth, peculiar muscles and hairy cover- 

 ing possessed by some men and women. The barnacle, once 

 a free-swimmer, is now a lazy ride-stealer, a freebooter and 

 pirate of the sea, threatening to scuttle the ship. Some 

 island insects and many varieties of birds have lost the 

 power to fly by long disuse of their wings, safety and food 

 not requiring flight. The whale has lost his ability to walk 

 on dry land. In general, when any organ has become 

 useless, it tends to retrogression, and finally becomes ru- 

 dimentary. Nature abhors the useless. But this rever- 

 sion is always slow, as Heredity is ever jealous of her 

 store. 



Reversions are but eddies in the great stream of Evolu- 

 tion, and like eddies show the direction of the current. It 

 is as though Nature had sent a courier back a little way to 

 guide us more clearl}' on in our investigations. This feature 

 ■of Evolution, theology should accept since it recognizes the 

 principle of " back sliding." The mites and ticks have 

 doubtlessly fallen from spiders and scorpions. The insect, 

 Stylops, with aborted wings, has sunk back from a free-flyer 

 to the ignoble life of a parasite. 



In closing this branch of the subject I will quote Prof. 

 Wilson : ^' While progressive Evolution develops the great 

 tree of life, extends each branch, clothes it with verdure, 

 and expands each blossom, it is degeneration which lops oft" 

 the worn and aged stems, prunes the weakly foliage, trims 

 the budding growths, and so directs and moulds the outlines 

 of the organic whole." 



PROOFS FROM MIMICRY. 



Mimicry, or the imitative faculty of some plants and 

 ■animals, gives us most interesting testimony for Evolution. 

 Some insects and birds, through the law of Natural Selec- 

 tion, in configuration and color are like the natural objects 

 over which they roam, thus securing a degree of protection 

 from their natural enemies. The brooding bobolink harmo- 



