424 NINETEEN'TH CENTURY. pt. hi. 



that there are very few close links to be found between fossil 

 animals ; but when we remember that nearly all the rocks in 

 the earth's crust are made out of others which have been 

 destroyed, it is scarcely wonderful that so few skeletons 

 should be found of those that were once buried, and it is 

 not likely that many of these would be just the intermediate 

 forms we want. Still some have come to light, for a bird- 

 reptile has been found in the rocks of Kansas, in America, 

 which has a skeleton like a bird, but teeth and jaws like a 

 reptile ; and a reptile has been dug out of the Stonesfield 

 slate in England, which Mr. Huxley says must have hopped 

 like a bird, having legs, neck, and a bird-like head, while it 

 had nevertheless teeth like a reptile. Again, horses have 

 been found in the rocks of America, which have sepa- 

 rate toes, and others in which the toes are beginning to 

 grow together, showing how they may have been gradually 

 altered into our one-toed horse. 



And here again, those who studied fossil animals asked 

 why these forms should succeed each other, gradually pas- 

 sing on into the living forms of our own day, which are all 

 slightly altered copies of these fossils of the rocks ? 



How can Plants and Animals have become altered ? — 

 It was questions such as these which seemed to call for 

 answers, and to find none except the one proposed by 

 Lamarck ; namely, that the different kinds of animals are 

 all descended from a few simple forms. If this were so, then 

 it would be quite natural that higher and higher forms should 

 appear gradually upon the earth, and that the kinds most 

 alike should follow directly upon each other, those which are 

 now living being very like their ancestors in the newest 

 formation in the earth's crust. It would also help us to 

 understand why animals of the same class should have the 



