54 CLASSIFICATION. 



In fact, in Natural History as in Religion, the old 

 proverb that " Doctors always differ/' finds a constant 

 application, although it must be confessed that in both 

 eases the more enlightened present a tolerably close 

 agreement in their views ; whilst a few, who may be 

 regarded as the Joe Smiths of Science, put forward 

 the most extraordinary systems, the only object of 

 which appears to be to show the world how inge- 

 niously their authors can twist and torture facts, so as 

 to escape from the beaten track which others are con- 

 tented to follow. Clever as some of these systems 

 may be however, one generally regards them with the 

 same feelings as the antics of one of those ingenious 

 artists who perform a very bad hornpipe on a tight 

 rope, or on the back of a galloping horse. The result 

 in both cases is undoubtedly curious, and shows what 

 may be done by perseverance ; but at the same time 

 we feel that so much industry might have been much 

 better employed. For this reason, in illustrating the 

 application of the foregoing principles to the classifi- 

 cation of Insects, we need not take any notice of 

 these out-of-the-way systems, which rarely exert any 

 influence on science. All that it is necessary to state 

 here with regard to differences of opinion in classifica- 

 tion, is, that in the present day Entomologists are 

 pretty equally divided between two methods of effect- 

 ing the primary division of Insects; in one of these 

 the highest importance is attributed to the structure 

 of the mouth in these creatures, whilst in the other 

 the nature of their metamorphosis is placed in the 

 first rank. The orders adopted are much the same 

 in both these systems, so that their comparison is 

 easily made. 



In the first-mentioned systems we are obliged in 



