430 ON THE TRIBES 



We now look for Mandihulata which have cyUndrical 

 larvae with membranaceous feet, and the genus Phryganea 

 appears to the view. 



Trichoptera. 



That the Urocerata, with their hexapod larvas, form an 

 osculant order between these and the true Hymenopiera, 

 cannot be doubted; they may, in pursuance to the custom 

 of naming orders from some peculiarity of the wings, be 

 called Bomboptera, in allusion to the unusual noise which 

 they make in flying, and from which they borrow their 

 French name of Ichneumons-Bourdons. The important 

 question, however, is, Whether the genus Terithredo of 

 Latreille, which is evidently farther removed from the true 

 liymenoptera than the genus Sirex, ought to be esteemed 

 osculant with it, or as constitutinjf a ganglion of the same 

 order in which Fhryganea is placed ? I confess that I am 

 rather inclined to adopt the latter alternative, however 

 contrary to the general opinion, and that for the following 

 reasons. 



ThePerZ«n«of the Genera Insectorum, or M. Lamarck's 

 family of Phrygajiidtc, is evidently a natural group formed 

 of those insects whose larvas, admirably described by Aris- 

 totle under the name of Xylopthori, are aquatic and Uve 

 in tubes or sheaths, which they have the instinct to make 

 for themselves. This group is lately divided by Latreille 

 into Perlides and Plicipoines, the last of which constitute 

 Mr. Kirby's order Trichoptera. Such a name, thus found- 

 ed on too trivial a character for an order, is perhaps ob- 

 jectionable not only as inapplicable to all Phryganea, but 

 because it places the genus Perla in another order, when 

 the larva, the metamorphosis, the ancemisB, the mouth 



