368 ON THE OEDERS 



The first reflection to occur on the inspection of this 

 table* will probably be, that Savigny has, in his " Tableau 

 des organes de la Bouche des Insectes Hexapodes Masti-^ 

 cateurs et Suceurs compares," given a proof that these re- 

 lations of analogy may extend even to the organs of man- 

 ducation. He has the rare merit, moreover, of using no 

 expression which would induce us to suppose that he con- 

 sidered them as proofs of direct affinity, although certain 

 authors, whose arrangement was founded on his observa- 

 tions have since reckoned them to be such. 



Our thoughts will next be directed to the inequality which 

 is so apparent in the contents of the orders. The order of 

 Diptera, for instance, comprises an almost innumerable 

 quantity of species, whereas those of Apterous insects are 

 well known to be remarkably few . Yet the order of Aptera 

 has been admitted as natural by every eminent entomolo- 

 gical writer since the days of Degeer. Why then this 

 disparity of contents in two adjoining groups ? Such is 

 truly a question well worthy of investigation, but more par- 

 ticularl}' when we know that this disparity is the strongest 

 argument in favour of a saltus that can be adduced. I 

 have, however, designated the great intervals which some- 

 times separate two such adjoining groups as chasms or 

 hiatus, rather than as saltus ; in the first place, because they 

 never appear to proceed from the series being interrupted 

 by any thing known ; and then, because I cannot help 

 thinking, from analogy, that if they never should be filled 

 by living animals, they may have, at some time or other, 



• The relations of analogy refer of course to the types of the correspond- 

 ing orders, rather than to all their contents; and the propername annexed 

 to the order is that of the person who applied fust the technical word, rather 

 than of him who has the greater merit of having detected the group. Of 

 the ten principal orders we owe four to Aristotle, one to Ray, one to Lin- 

 ux us, and four to Degeer. 



