502 On Synthetic Types in Insects. 



that unite by themselves the bees, moths, and flies. Thus 

 there are certain Hemiptera ( Corixu) that resemble the 

 coleopterous genus Brachys ; Forficula is analogous to the 

 Staphylinidae, and Blatta may be said to resemble some 

 Lampyridoe. The close affinities between the Orthoptera 

 and Neuroptera hardly admit of these analogous forms, 

 though we find them still. Here again we see the isola- 

 tion of the Coleoptera from the other sub-orders with 

 which it is connected. The sub-orders below it, by an 

 exact parallel with the case above mentioned, reach up 

 and connect themselves by these remarkable analogies 

 with the Coleoptera, which do not in turn assume any 

 of their forms. Some Orthoptera are very coleopterous- 

 like, and some Hemiptera are very coleopterous-like. The 

 reverse cannot be said. So the Diptera and Lepidop- 

 tera, as they advance in their family forms, are constantly 

 throwing out hints and suggestions of forms that seem 

 very strange to them, but become generalized in the 

 group that tops them. Thus in the broad, irregularly net- 

 veined, neuropterous fore-wing, which becomes smaller 

 and thicker in the orthopterous Blatta, and still more 

 coleopterous in the hemipterous Corixa, we arrive at the 

 perfected elytron, with its regular, obsolete veins, and 

 new protective function. 



Most of the examples above mentioned are familiar to 

 entomologists, and others will occur no doubt to illustrate 

 the subject more fully. 



Many authors have agreed that the sub-orders of insects 

 can be arranged into two series or groups, often called 

 Mandibulata and Haustellata, though disagreeing as to 

 the relative rank of these two divisions, and the true 

 places the sub-orders should occupy within them. It is 

 enough for my purpose to assume that there are two 

 such series, though believing that the two culminate in 

 the Hymenoptera and Coleoptera respectively, in the suc- 

 cession that I have indicated above. 



