NEUROPTKRA. 415 



reservoirs similar to those of caterpillars, and that are also produced by fusi 

 situated in the lip. The interior of the habitation forms a tube which is open 

 at both ends for the intromission of water. The larva always transports its 

 domicile along with it, protrudes the anterior extremity of its body while 

 progressing, never quits its dwelling, and when found to do so, returns to it 

 voluntarily when left within its reach. 



When about to become nymphs, they fix their tubes to different bodies, but 

 always in water, and close the two orifices with a grating, the form of which, 

 as well as that of the tube itself, varies according to the species. In fixing 

 their portable dwelling, they so manage it that the aperture, which is at the 

 point d'appui, is never obstructed. 



The nymph is furnished anteriorly with two hooks, which cross each other 

 and somewhat resemble a rostrum or snout. With it, when the period of its 

 last metamorphosis has arrived, it perforates one of the grated septa in order 

 to procure egress. 



Hitherto immoveable, it now walks or swims with agility, by means of its 

 four anterior feet, which are free, and furnished with thick fringes of hairs. 

 The nymphs of the large species leave the water altogether, and climb on 

 various bodies, where their final change is effected. The small ones simply 

 rise to the surface, where they are transformed to winged insects, in the 

 manner of the Culices and various Tipulariae; their exuvium serves them 

 for a boat. 



There are several subgenera. 



ORDER IX. 



HYMENOPTERA*. 



IN this family we still find four membranous and naked wings, and a mouth 

 composed of mandibles, maxillae and two lips ; but these wings, of which the 

 superior are always largest, have fewer nervures than those of the Neuroptera, 

 and are not veined ; the abdomen of the females is terminated by an ovipositor 

 or sting. 



Besides their compound eyes they are ah 1 provided with three ocelli. Their 

 antennae vary, not only according to the genus, but even in the sexes of the 

 same species ; generally, however, they are filiform or setaceous. The maxillae 

 and labium are usually narrow, elongated, and fixed in a deep cavity of the 

 head by long muscles, form a semitube inferiorly, are frequently folded up at 

 their extremity, and better adapted for the transmission of nutritious fluids 

 than for mastication ; in several they form a proboscis. The ligula is mem- 



Membrane- wi nged . 



