13 



to say unphilosopliical, and directly opposed to the very prin- 

 ciples upon which the argument of design is based. On the 

 other hand, they form one of the strongest witnesses to evohi- 

 tion. They may be said to be a necessary part of it ; for, were 

 any abrupt changes of structure constantly occurring, Ave should 

 at once begin to infer that some power was as constantly at 

 work to interfere and make such changes, somewhat after the 

 notions of the cataclysms and recreations of early geological 

 theorists. When such sudden breaks appear to occur, the 

 balance of probability is greatly in favour of the inference of 

 the previous existence of, but now extinct forms, which once 

 united such well-differentiated types as may now exist. 



It may be objected that I have regarded rudimentary organs 

 too much in the light of atrophied conditions, and not as origins 

 for future development ; and it is worth while observing that 

 there are two ways of regarding them, both, however, equall}^ 

 in harmony with the doctrine of evolution ; and in many cases 

 it is at present impossible to say with certainty which would 

 be the correct view. Thus, in the case of the lizards, it may 

 be that the condition of the limbs of the Pseudopus, which 

 are rudimentarj^ and concealed beneath the skin, was the fore- 

 runner of the state of the limbs represented by the other genera 

 given above. We cannot say. The argument, however, is 

 equally sound on either supposition. On the first, the design of 

 the limbs dies out, and is replaced by the snake-like method of 

 progression ; on the other, the latter mode of locomotion gra- 

 dually disappears, and is replaced by limbs. 



Design No. 2. — I must now consider the second instance of 

 design, or use.* Having acknowledged an organ, as the eye, 

 to be designed, we see design in the use of it. Here is the 

 supposed stronghold of the teleologist. Many organs seem so 

 obviously intended for definite uses, that they love to dilate 

 upon the requisite adaptations which conspire to fulfil the use 

 of an organ. Thus no one can deny the use of sight to the 

 eye, or hearing to the ear, and so forth. And no one can deny 

 that the mechanism or structure of such organ is most admir- 

 able. But natural theologians very often go too far, and try to 

 discover a use in everything ; the result is, they not unfrequently 



* It will probably be felt immediately that, as a general rule, structure 

 and use stand or fall together. But there are some instances where an organ, 

 by its elaborate or peculiar structure, seems to justify a purpose, yet that 

 purpose may remain undiscovered. Such, for example, was the spleen. 

 When, however, we see an organ with a decided use, as the leg of a lizard, 

 which is used for running, I repeat that we are justified in describing such 

 an organ as useless when it remains concealed, in a rudimentary condition, 

 under the skin. 



