484 



NEUROPTERA 



metamorphosis inasmuch as the larva, instead of lying free, con- 

 structs a cocoon in its case or other habitation in which to change 

 to a nymph. In the larvae that do not make use of a portable 

 case the abdominal hooks are not essential, and are replaced 

 by other organs differing much in structure, being sometimes 

 apparently of a sensitive natiire, in other forms possibly respira- 

 tory. Miiller tells us of a carnivorous larva of this group in 

 which the anterior legs are armed with powerful forceps for pre- 

 datory purposes. 



The Hydroptilides comprise the most minute of the 

 Phryganeidae, and their species will prob- 

 ably prove to be very numerous in well- 

 watered tropical regions, though few have 

 yet been described from there. The per- 



viac- 

 "with 

 larva 



feet Insects (Fig. 320) bear an extreme 

 resemblance to small moths of the group 

 Tineidae. The larvae (Fig. 329) are des- 

 titute of respiratory filaments, and con- 

 struct portable cases of a variety of 

 forms, some resembling seeds. Miiller has 

 given particulars of a curious nature as 

 to' the cases of some Brazilian Hydrop- 

 tilides ; one species moors its dwelling 

 to a stone by means of a long silken 

 cable, by this artifice combining safety 

 with the power of ranging over a con- 

 ^' siderable extent of water. In Diaulus 

 there is only a narrow slit at each end 

 of the case, but one side of it is provided with two chimneys to 

 permit the flow of water for respiratory purposes. 



The larva of Oxyethira (Fig. 330) is a curious form, possess- 

 ing comparatively long legs, and a head and thorax slender in 

 comparison with the distended hind body. The cases are 

 fastened, for tlie purposes of pupation, to a leaf of a water-lily. 



Some very curious anomalies as regards the development 

 of the wings exist in the Phryganeidae ; Anomalopteryx, for 

 instance, has the wings quite short and useless for flight in 

 the male, while in the other sex they are ample ; in Enoicyla, 

 — the curious Insect figured on p. 481, in which the larvae 

 are of terrestrial habits — we find the females with only rudiments 



Fia. Zi'i.—Hydropiila 

 lachlani. B, Ca.se 

 larva magnified ; A, 

 more magnitied, 

 Klapalek.) 



