4 BRITISH APHIDES. 



Cercopidse.* Apliis, therefore, liere for the first time 

 asserts its claims to the antiquity of its race. 



Our present geological evidence will, therefore, lead 

 us to place the Hemiptera fourth in the order of birth 

 in primeval time, and thus to place the Diptera, the 

 Hymenoptera, and the Lepidoptera last on the list. 

 This sequence might, indeed, have been partly inferred, 

 if we take into account the connection shown by our 

 modern existent orders with phanerogamous plants. 



The following may be assumed as the order in which 

 insects appeared, as set forth by known fossil remains. 



1. Neuroptera. Devonian beds. 



2. Orthoptera. Coal-measures. 



3. Coleoptera. Carboniferous series. 



4. Hemiptera. 



,, Heteroptera. Permian and Lias. 

 ,, Homoptera. Lower Oolite and 



Purbeck. Aphis. 



5. Diptera. Upper Oolite, Solen- 



hofen limestone. 



6. Hymenoptera. Solenhofen. Apis. 



7. Lepidoptera. Solenhofen ? Sphinx. 



Koch has described several fossil genera allied to 

 the minute IViysanura, which have been preserved. 

 Such being the case, we may not think it hopeless 

 that yet more evidence will turn up of the occurrence 

 of Aphides in ages long past, where climatal and other 

 conditions permitted. 



The number of described living insects, Mr. Bentham 

 tells us, exceeds that of all known plants. Some ten 

 years ago Glerstaecker stated that the former exceeded 

 one hundred and sixty thousand. Mainly through the 

 pregnant hy]3othesis of Mr. Darwin, a considerable 

 stride has been made, as to deduction and correlation, 

 from materials supplied by these descriptions ; so that 

 now Entomologists less acutely may feel the charge 



* Vide a compendious treatise by Mr. Herbert Goss on the ' Geological 

 Antiquity of Insects.' Van Voorst, 1880, 



