THE TEE-ADAMITE EARTH. 



first ages, and those of the more perfect in the later ones. As in 

 the former cases, however, the actual results of observation are 

 altogether opposed to this. Of the eleven orders of Annulata 

 called into existence during the Palaeozoic age there are three 

 orders of insects the C<t>leoptera, Orthoptera, and Neuroptera ; 

 one of the Arachnida, four of Crustacea, one of Cirrhipeds, and 

 two of Annalids. Thus, as in the former case, all the classes are 

 fairly represented. But we find further in these classes, among 

 the three orders of Insects and four of Crustacea, the most per- 

 fectly organised of each class. We have therefore, in the case of 

 the Annulata, the same results as were obtained in reference to 

 the other two great divisions of the animal kingdom the most 

 perfectly organised being produced in the earliest ages ; and not 

 only was this the case, but they even there obtained their greatest 

 development. 



538. Although, as we have already stated, the Vertebrata present 

 striking facts in favour of the supposition of progressive improve- 

 ment already mentioned, a due examination of all the circum- 

 stances attending their gradual development, will show that no 

 real progressive organisation has been manifested in them. 

 If the supposition of progressively improving organisation 

 were well founded, it must be expected that the Vertebrate 

 animals of less complete organisation alone would appear in 

 the Palaeozoic age. We find on the contrary among the three 

 orders of Vertebrata which appeared in that age, the Saurian 

 reptiles and the Placoid and Ganoid fishes. Now, although 

 mammifers and birds did not appear, the reptiles which did 

 appear have a superior organisation to other orders which 

 appeared later, such as serpents and Amphibia. The fishes of this 

 epoch also are evidently superior in their organisation to many 

 of the orders which appeared later. Although, therefore, only two 

 of the four classes of the Vertebrata appeared during this age, 

 of these two the most perfect specimens appeared the earliest, 

 in contradiction to the supposition of progressively increasing 

 perfection of organisation. 



The Triassic age presented traces of the existence of the order 

 of birds called Waders, and of Chelonian reptiles (tortoises). It is 

 curious here to find at an epoch so remote in the history of 

 the globe, birds the most perfect of the aerial Vertebrata, and the 

 Chelonian reptiles, the most perfect of their class. 



The Jurassic age presented no new orders of Vertebrata. The 

 Cretaceous age presented one order of birds, the Web-footed ; 

 two of fishes, the Cycloids and Ctenoids, both less perfect than 

 those of the Palaeozoic age. 



It was only, therefore, during the Tertiary age that the other 

 148 



