HI LECTURES ON EVOLUTION 85 



great group of Lizards, which abound in the 

 present world, extends through the whole series 

 of formations as far back as the Permian, or latest 

 Palaeozoic, epoch. These Permian lizards differ 

 astonishingly little from the lizards which exist 

 at the present day. Comparing the amount .of 

 the differences between them and modern lizards, 

 with the prodigious lapse of time between the 

 Permian epoch and the present age, it may be 

 said that the amount of change is insignificant. 

 But, when we carry our researches farther back 

 in time, we find no trace of lizards, nor of any 

 true reptile whatever, in the whole mass of for- 

 mations beneath the Permian. 



Now, it is perfectly clear that if our pala3onto- 

 logical collections are to be taken, even approxi- 

 mately, as an adequate representation of all the 

 forms of animals and plants that have ever lived ; 

 and if the record furnished by the known series 

 of beds of stratified rock covers the whole series 

 of events which constitute the history of life on 

 the globe, such a fact as this directly contravenes 

 the hypothesis of evolution ; because this hypo- 

 thesis postulates that the existence of every form 

 must have been preceded by that of some form 

 little different from it. Here, however, we have 

 to take into consideration that important truth 

 so well insisted upon by Lyell and by Darwin 

 the imperfection of the geological record. It can 

 be demonstrated that the geological record must 



