CLASSIFICATION. 



37 



There can, of course, be no finality on such a question, seeing 

 that so little cau possibly be demonstrated regarding* it; but if it 

 is of any use to discuss it at all it seems by no means impossible 

 that the ancestor of the Coleoptera is to be found among the 

 ►SialidyE (JNeuroptera-Planipennia) in an extinct group possessing 

 the more complete metamorphoses of the Sialides, and with larvae 

 possessing the terrestrial habits and subcortical habitat of the 

 Raphidiides. The true position of the Coleoptera, however, 

 with reference to the other orders of insects, is quite uncertain, 

 and they cannot be placed in close proximity with any. We are 

 entirely in the dark as to their phylogeny, and all that has been 

 said regarding it is only more or less unwarrantable hypothesis. 



Classification. 



In writing a general introduction to the Coleoptera for a work 

 like the present, of which the various sections will be the production 

 of several authors, the question of classification is by far the most 

 difficult to deal with, for, naturally and probably, in the present 

 state of our knowledge, individual authors may refuse to be 

 bound by any system that may be laid down. It should therefore 

 be understood that there is no intention to bind the specialists 

 who may hereafter take part in the work, and in their prefaces 

 and introductions they can, of course, adopt any classification of 

 their groups and families that they think fit. 



One thing is certain, and that is that any linear classification is 

 quite out of the question. The attempt to force this has been the 

 chief cause of the confusion that has arisen. The great groups 

 must be regarded as more or less parallel series, arising, hypo- 

 thetically, from common stocks whose origin is quite unknown, for 

 (so far as we at present know with certainty) they have appeared 

 in geological strata in several instances simultaneously, and their 

 remains, where found, are equally and fully developed. 



The earliest writers after Linne, in their systems of classifica- 

 tion, laid the chief stress on the variation of the number of joints 

 in the tarsi, Olivier being the first to adopt the primary sections 

 of Pentamera, Heteromera, Tetramera, and Trimera ; this division, 

 modified and enlarged by Latreille and others, has been in use up 

 to quite recent times, and must of course be always taken into 

 consideration. 



In 1883 Leconte and Horn published their 'Classification of 

 the Coleoptera of North America,' which, although in many points 

 not in accordance with the views of modern Coleopterists, was yet 

 a distinct advance on anything that had preceded it. They divided 

 the order into two primary divisions : — 1. Coleoptera (genuina), 

 having the mouth-parts normal, the palpi always flexible, the gular 

 sutures double, at least before and behind, and the prosternal 

 sutures distinct ; and 2. Bhynchophora, having the head more or 

 less prolonged into a rostrum, the palpi rigid (except in Ehijso- 

 MACEmDiE and Antheibii)^:), the gular sutures confluent along the 



