SYSTEM OF INSECTS. 4-07 



in the thalerophagousand saprophagous Lamellicorn ones; 

 in the Anoplura and Thysanura; the Chilopoda and 

 Chilognatha amongst Apterous insects ; in the Scorpion- 

 idea and Aranidea amongst the Arachnida ; and in the 

 Macrura and Brachyura amongst the Decapod Crus- 

 tacea. Again, in other cases three seems to be the most 

 prominent number: this takes place sometimes with re- 

 gard to the primary groups of an Order, or what I de- 

 nominate the Suborders. Thus we have the Diurnal, 

 Crepuscular, and Nocturnal Lepidoptera a ; the Linnean 

 genera Blatta, Mantis, and Gryllus constitute the Or- 

 thoptera ,- and other instances of this number might be 

 produced in some minor groups. But that which ap- 



* Dr. Horsfield, in his very ingenious and generally admirable De- 

 scriptive Catalogue of the Javanese Lepidoptera in the Museum of 

 the Honourable East India Company, has divided that Order into 

 Jive primary groups, apparently to accommodate it to Mr. W. S. 

 MacLeay's quinary system. I trust he will pardon me for observing, 

 that in this arrangement he seems to me rather to force than to 

 follow nature ; and that though he adheres to the above system as 

 to the number, he forsakes it in the construction of his groups. 



The obvious primary sections of the Lepidoptera, which have 

 been evident to almost every one who has at all studied the Order, 

 are the three named in the text, corresponding with Linne's genera 

 Papilla, Sphinx, and Phakena. The groups of the last or nocturnal 

 section, which Dr. Horsfield has elevated to the same rank with the 

 two first, are evidently not of equal value, nor to be phced upon the 

 same platform ; for the Bombycida, Noctuidte, and Phattnidtff, are 

 clearly of a secondary rank. Indeed this section ^is resolvable into 

 more groups of equal value than the learned Doctor has assigned to 

 it ; for the Tortricidce, Tineidce, &c. are not so united to the Geo- 

 meters, or genuine Phalcenidce, as to form with them a primary group 

 of the Nocturnal Lepidoptera, but are themselves entitled separately 

 to that distinction. This will be evident to every one who will take 

 the trouble to compare the larvae and their habits, of the two tribes, 

 as well as the perfect insects. 



In the construction of his groups, he seems not to have discovered 

 in the Lepidoptera a great typical group resolvable into two, or at 



