the British Neurojjtera-PIanipennia. 211 



" Among generic characters the dentation of the man- 

 dibles stands pre-eminent. It remains constant through- 

 out every moult. I therefore describe it together with 

 the full-grown larva. The head is dark brown ; the soft 

 fore-part of the upper lip and the front border of the 

 accessory part are white. The upper mandibles are 

 strong, horny, triangular, their tips somewhat curved 

 inwards ; on the inner edge is a short blunt tooth, 

 followed by a still shorter one, beyond which the man- 

 dibles increase considerably in breadth ; the inner edge 

 below these teeth is slightly concave. The lower man- 

 dibles have a broad basis, connected by a membrane 

 with the under lip ; the stalk and the hooks may be de- 

 scribed as composing an angle; the hook is somewhat 

 horny, and bears a round membranous masticatory 

 piece, which in front and on the inner edge has very 

 short points and is rough ; on the outer side of these 

 parts are the maxillary palpi, which are four-jointed, the 

 first three joints almost equal, cylindi'ical, gradually 

 diminishing in thickness, the last joint conical ; the labial 

 palpi are placed close together, short and thick, with two 

 cylindrical basal joints, and one conical end-joint, which 

 is as long as the other two united. The antennas dis- 

 tinctly protrude ; the first two joints are short, thick, 

 and cylindrical ; the third is thin, and twice as long, 

 cylindrical at the base, thickened towards the end, and 

 therefore somewhat clavate ; the fourth is narrow, slightly 

 spindle-shaped or cylindrical, provided at the end with 

 three short points in very young larvae." 



" The large eyes lie behind and a little beneath the 

 antennae, exactly on the sides of the head; they are 

 slightly contracted, and thus give the larvas a strange 

 appearance. On the clypeus and frontal and posterior 

 plates of the head stand solitary bristle-like hairs. The 

 head is not closely connected with the first thoracic seg- 

 ment, as the intervening membrane is considerably 

 wade ; beneath the latter there runs a fine, slightly 

 curved, horny ridge. The pronotum is horny, broader 

 than long, quadrangular ; on its hinder edge, on each 

 side, is the first spiracle. The other thoracic segments 

 are membranous above, and bear only isolated small 

 horny plates, a larger one in the middle, and two smaller 

 ones on each side, on which stand solitary short bristle- 

 like hairs ; these plates vary somewhat in different 

 species." 



p 2 



