[11] 



COLLECTING AND PRESERVING INSECTS RILEY. 



The relation of tliese sixteen orders to the older, septenary scheme is 

 shown by the following arrangement: 



1. Hymenoptera . .Hymen optera XY. 

 Coleoptera Coleoptera X. 



3. Lepidoptera .... Lepidoptera XIY. 



( Homoptera. 



4 Hemiiiteri I Hemiptera, IX ) Heteroptera 



4. Memipteia ^ Thysanoptera YIIl. 



5. Diptera \ Diptera XYI. { I^cl^^^ling Aphaniptera or Si 



.. ,1 , ( Orthoptera YII. 



Orthoptera ^ Dermaptera YL 



\ phonaptera of some anthors. 



7. Xeur optera. 



fTrich optera XIII i 



Mecoptera XII [• Xenroptera. 



Xenroptera XI ) 



Platyptera Y ^ 

 ] Plecoptera lY | 



Odonata III J> Pseudo-nenroptera. 



Ephemeropterall | 



Thysanura I J 



It will be seen that the changes are not so great as wonld at first 

 appear. The three more important orders, namely, the Hymenoptera, 

 Coleoptera, and Lex)idoptera, remain substantially the same in all clas- 

 sifications, and so with the three orders next in importance — tlie Hem- 

 iptera, Diptera, and Orthoptera. All that has been done with these 



JJiajram in 



Fig. 3.— Cross section of Fig. 2. 



three has been to rank as separate orders what by former authors 

 were preferably considered as either families or suborders. The princi- 

 pal change is in the Xenroptera, of which no less than eight orders have 

 been made. This is not to be wondered at, because the order, as for- 

 merly construed, was conceded to be that which represents the lowest 



