448 



NEUROPTERA 



The species are rather numerous, and have been recently 

 monographed by Albarda.^ The three or four British species 

 of the genus are all rare Insects, and occur only in wooded 

 regions. 



Tlie Eaphidiides, like the Sialides, have a carnivorous larva, 

 which, however, is terrestrial in habits, feeding, it would appear, 

 chiefly on Insects that harbour in old timber. The snake-fly 

 larvae (Fig. 292) are very ingenious in their manner of escaping, 

 which is done by an extremely rapid wriggling backwards. They 

 are capable of undergoing very prolonged 

 fasts, and then alter in form a good deal, 

 becoming shorter and more shrivelled ; 

 rig. 292 is taken from a specimen that 

 had been fasting for several weeks. They 

 are excessively voracious, and hunt after 

 the fashion of beasts of prey ; their habits 

 have been described by Stein,^ who states 

 that he kept a larva from August to the 

 end of May of the following year without 

 food ; it then died in a shrivelled- up state. 

 The larva of the snake-fly changes to a 

 pupa that is remarkably intermediate in 

 form between the perfect Insect and the 

 larva ; the eyes, legs, wing-pads, and ovi- 

 positor being but little different from those 

 of the imago, while the general form is 

 Fig. 2^2.Raphidia notata, ^i^^t of the larva, and the peculiar elonga- 



larva. New Forest. , , i p i ^ 



tion of the neck oi the imago is absent. 

 This pupa differs from that of Sialis in the important particular 

 that before undergoing its final ecdysis it regains its activity and 

 is able to run about. 



The internal anatomy of Rapliidia has been treated by Loew,-^ 

 and is of a very remarkabla character ; we can liere only mention 

 that the salivary glands consist of a pair of extremely elongate 

 tubes, that there is a very definite paunch attached as an ap- 

 pendage to one side of the crop, and that the most peculiar 

 character consists of the fact that, according to Loew, four of the 

 six Malpighian tubes have not a free extremity, being attached 



1 Tijdschr. Ent. vol. xxxiv. 1891. ^ Arch.f. Naturg. iv. i. 1838, p. 315. 



^ Linnaea entomologica, iii. p. 1848, 346, pi. i. 



