02 NINETEENTH CENTURY. PT. Hi, 



skeletons should be found of those that were once buried, 

 and it is not likely that many of these would be just the in- 

 termediate 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 Stones- 

 field 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. Agn'n, 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 pass- 

 ing 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 

 same bones, and why some should have parts remaining in 

 their body which are no longer of any use ; and lastly, it 

 would explain why naturalists have so much difficulty in 

 distinguishing nearly related species. 



But though these reasons made it seem very likely that 



