334 AUSTRALIAN I'SVLLID.K, 



Trioza TRISTAN le, 11. sp. (Plates iv., fig. 13; v., fig. 12). 



Larva light brown, with central portion darkest on dorsal 

 surface, thickly clothed with Houry secretion; flat, slightly con- 

 cave, circular, fringed with very fine semitransparent filaments 

 truncated at tips. Segmental divisions and dorsal stripe from 

 behind; head pale yellow, eyes and antennae hidden from above, 

 only tips of tibiae and tarsi showing beyond edge of shield. 

 Ventral surface aw^ollen, yellow. Head very small; antennae short, 

 stout, turned in, and just projecting be3'ond edge of shield, ros- 

 trum very short, brown at apex. Legs stout, swollen, tips of tarsi 

 3^ellow, furnished with a circular disc at apex. 



FuiJa not differing from the last larval stage except in size. 



Imago. — Length 0*06, antenna? 0-0175 inch. General colour: 

 head, legs, antenm^ and thorax light reddish-brown; apical third 

 of antennae fuscous, eyes purple, ocelli red, abdomen pale yellow. 

 Wings transparent, nervures light brown. Head very short, but 

 broad across, arcuate in front, lobed, a deep median suture, round 

 at sides and deeply arcuate, in centre of hind margin. Face lobes 

 short, conical, hidden from above, clothed wdth hairs. Antenna? 

 long, slender; 1st, 2nd joints short, stout; 3rd longest: 9th-10th 

 short, thickened, rounded at apex. Eyes very large, hemispheri- 

 ■cal; lateral ocelli close to hind margin of eyes, central ocellus at 

 base of median cleft, hidden from above. Thorax : pronotum 

 slender and narrow at junction with head, rounded in front, 

 truncate behind; dorsulum very prominent, convex, narrow, 

 truncate in front, produced into a large l)lunt spine on sides, 

 sloping behind to truncate apex; mesonotum large, deeply arcuate 

 in front but swelling out on either side of dorsulum, rounded 

 behind; scutellum large, angulated. Legs very long, slender, 

 clothed with tine hairs, femora usually thickened, tarsi large, 

 apical margin of tibiae of hind pair furnished with two stout 

 spines on inner edge. Wings long, slender, more than thrice as 

 long as broad, primary stalk long, stalk of subcosta short; radius 

 short, straight, coming out on upper margin of wing, forming a 

 iilender narrow pointed cell, upper branch of cubitus long, curving 



