| | wings. | | | |----------+----------+------------+----------+-----------+---------------| | VII. NEUROPTERA. | | Various. | Various. | Various. | Various. | Various. | Various. | +----------+----------+------------+----------+-----------+---------------+ The very imperfection of this table will constitute its principal utility, because, instead of acknowledging variety as a suitable definition of any particular part or state, the differences of which in respective classes, entomologists have been accustomed to consider characteristic, we find authors labouring to confine a group by what they would wish to consider good and solid characters, which characters they often at last leave so comprehensive, as not only to include the class which they had originally intended to define, but also a majority of those other classes which they had supposed previously disposed of. If, in reply, my reader should tell me that my seventh class was somewhat of this too comprehensive kind, I should simply reply that I intended it to be so; and if my reader happen to know a better, he can interline it in his copy. A space would then be occupied, which has hitherto in all such definitions been really, although not verbally, vacant. It is hard to break through the trammels of habit; it is hard to give up what one has for a long time taken for granted; it is hard to relinquish favourite schemes, however untenable: an innovator, however, is bound to deliberate well and coolly,--is bound to try all the various schemes before him with the test of reason. If the entomologist do this he will find his positive knowledge much less than he expected,--he will perceive that he is book-wise and fact-foolish; if, therefore, he would wish to arrive at truth, he must strip himself of his borrowed garments and all the theoretical dogmas he may have, however incautiously, imbibed, and trust entirely to what he has discovered himself, or what has been discovered by those who had no theory to support but truth,--no end to answer but amusement; for your theoretical writers, if they meet with a fact which militates against a favourite theory, will too often suppress it entirely, and on the same principle are ever anxious to magnify to an unnatural size, any slight, and often imaginary, circumstance, which they consider may tell in their favour. Among theories that have been thus established on very weak and insufficient foundations are all dichotomous divisions, especially those in which one group is defined as possessing and the other as wanting any fixed and peculiar character; a definition, by the by, applicable to nearly all dichotomies: the dichotomy to which I have here to allude is the division of insects into Mandibulata and Haustellata. Now every division founded on the presence or absence of a particular character