134 THE ADVANCE OF SCIENCE 



in the vast interval of time which has 

 elapsed between the deposition of the 

 earliest fossiliferous strata and the pres- 

 ent day. There is no reasonable ground 

 for believing that the oldest remains yet 

 obtained carry ns even near the begin- 

 nings of life. The impressive warnings 

 of Lyell against hasty speculations, based 

 upon negative evidence, have been fully 

 justified ; time after time, highly organ- 

 ised types have been discovered in forma- 

 tions of an age in which the existence of 

 such forms of life had been confidently 

 declared to be impossible. The western 

 territories of the United States alone have 

 yielded a world of extinct animal forms, 

 undreamed of fifty years ago. And, wher- 

 ever sufficiently numerous series of the 

 remains of any given group, which has 

 endured for a long space of time, are 

 carefully examined, their morphological 

 relations are never in discordance with the 

 requirements of the doctrine of evolution, 



