S90 ON INSECT ANATOMY. 



insect structure, derived from a given source, is of greater value 

 than vague statements gathered from the general surface of insect 

 history ; and secondly, because I have not met with any detailed 

 account of the anatomy of the cricket in our science journals, 

 although the creature is familiar to us as household words. Another 

 reason for my selection was, that the insect is always to be got, so 

 that any spare time could be given to its examination, without fear 

 of being forced to leave the work incomplete for want of material. 

 For the same reason, also, anyone can obtain and examine it for 

 himself, and so be in a position to criticise and correct my results. 



In this communication I limit myself to the descriptive anatomy 

 of a single insect because the lessons to be learnt from each example — 

 whatever be the one selected — are best learnt by an exhaustive study 

 of it, no part or detail being omitted on the supposition of its being 

 already known. Facts freshly observed, and communicated direct 

 by the observer, impress more, and come with more interest than 

 statements compiled from works already known. Even if not new, 

 they have, for the time and purpose, the freshness of re-discovery, and 

 a lasting value if they settle what was not definitively accepted. 

 !N'or is the time spent in such examinations disproportionate to the 

 results gained. For the anatomy of a single insect not only illus- 

 trates that of all its kind but also affords a vantage-ground from 

 which we get an insight into the general nature of insect organisms, 

 and recognise variations and contrasts as well as likeness of struc- 

 ture, so that time is saved in all subsequent investigations. Each 

 onward step gives us possession of new standards of comparison 

 whereby to interpret structural peculiarities, and additions or 

 omissions of parts and organs and lastly, any one item in the long 

 series of facts may throw unexpected light upon phases of 

 development, and so help to widen the basis upon which higher 

 generalisations may be founded. 



"What has hitherto been accomplished in insect anatomy has been 

 of great service in furthering the purposes of the entomologist, as 

 well as of the comparative physiologist. It is so obvious as scarcely to 

 need remark, that classifications once based on external appearances 



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