1911] Muir and Kershaw — Mouth-parts of Hemiptera 9 



held by the barbed tips of the mandibular setae. It seems highly 

 improbable that long slender rods like the setse could pierce a 

 chitinous insect without some support near their tips. Carniv- 

 orous bugs almost invariably suck their prey whilst it is suspended 

 from the tip of the rostrum, the bug meanwhile resting head 

 downwards; they often retain their hold on the prey and continue 

 to suck out its contents whilst the labium is withdrawn against 

 the ventral plates of the head and thorax — its usual position when 

 at rest. This feat would be impossible unless the prey was held by 

 the barbed tips of the mandibular setse, whilst the maxillary 

 setse were used to search the interior of the body for juices. 



Note A. (Fig. 14) 



This interpretation differs both from Uzel's and Garman's, 

 and is founded upon observations of a head of one of the Tuhuli- 

 fera common in the flower of the sugar cane in the Mossman 

 district (North Queensland). We figure this head and give the 

 following short description to prove our homology. 



The head-capsule is of the usual Thrips type, being deflexed 

 and inflexed, the mouth-parts being brought between the front 

 legs, as in Homoptera. The anterior edge of the head-capsule 

 (the oral margin) is strengthened by a thick rim of chitin (/). 

 From this rim arise two short pillars (fc), one on each side, above 

 the maxilla, which proceed backward into, and sub-parallel with 

 the wall of, the head-capsule. At the distal end of these pillars 

 are articulated, by a perfect ball and socket joint (Fig. 14, z), the 

 mandibular setse. Beyond these pillars are two stout conical pegs 

 arising from the head-capsule, evidently for the attachment of 

 muscles. The clypeus (clr) is well developed and slightly asym- 

 metrical, the left basal corner being emarginate. The labrum 

 (lb) is small, with its lateral edges bent round ventrally to form 

 a semi-tube. The right maxilla is formed by a sub-triangular 

 plate (Fig. 14a. mxp), the palpus arising from a membranous part 

 of the center; the left maxilla is asymmetrical, a membrane sep- 

 arating the sub-triangular distal part, bearing the palp (Fig. 14 y. 

 mxp. b.), from the rounded basal part bearing the seta (Fig. 14 

 y, mxp. a. and max. s.). This basal part is capable of movement 

 apart from the distal part, and carries the seta along with it. 

 The anterior edges of the maxillae meet in the medial line beneath 



