SEPTENARY SYSTEM. 249 



dependent on the Alary, Maxillary, and Metamorphotic Systems, 

 I beg to say, that on these three systems are founded all 

 others which owe their existence to scientific inquiry, unas- 

 sisted by theory. Latreille in France, Burmeister in Germany, 

 and Kirby in England, themselves, lonyo intervallo, at the head 

 of Entomology in their respective countries, have reviewed the 

 labours of others, and each proposed what he imagines a more 

 perfect system than any previously existing. These three 

 systems have been styled Eclectic ; they are very similar, and 

 are all of them founded exclusively on those characters which I 

 have shown to constitute the Alary , Maxillary , and Metamorphotic 

 Systems, and which harmonize so beautifully with the Septenary. 

 These Eclectic Systems are entirely practical ; there appears no 

 leaven of theory to be found in either of them. They may be 

 called linear series of insects, arranged with every possible 

 attention to structural differences. 



These Eclectic Systems, however, do not numerically accord 

 with the Septenary ; and this difference does not arise solely 

 from the erection of isolated animals of anomalous structure, as 

 the earwig, flea, Stylops, &c, into groups of equal value with 

 Hymenoptera and Coleoptera, containing almost myriads of 

 species. With this practice I consider it would be childish to 

 combat. A large group, Triclwptera, comprising the Pkn/qa^ 

 nina, has been separated from Neuroptera by Mr. Kirby. 

 This author has not, at least I cannot find that he has, ex- 

 plained why the Phryganina should be separated from the 

 Neuroptera generally ; but he uses very elaborate arguments 

 to prove the propriety of their being separated from the Perlina 

 in the same class. " Whoever examines," says Mr. Kirby, "the 

 several tribes into which Mr. MacLeay has divided the Neu- 

 roptera, will observe, in all of them, a distinct prothorax, a 

 circumstance which they possess in common with those orders 

 (classes) that use their mandibles for mastication ; whereas, in 

 those which do not use them for mastication, as the Hymenop- 

 tera, or that take their food by suction, this part is replaced 

 by a mostly narrow collar forming a part of the alitrunk : the 

 existence then of the prothorax in the Perlidcv, and of the collar 

 in the Trichoptera, affords no slight presumptive evidence that 

 they belong to different orders (classes)." I think this argu- 

 ment will scarcely bear a keen investigation. The premises 

 are not sufficiently sound. It may be objected that the pro- 



