ON SOME AUSTRALIAN TERMITES. 



367 



Head (fig. 4) very large and broad, rounded behind, with a pale median suture 

 from posterior margin forwards, widest behind the middle, sloping in towai-ds the 

 antennae, bearing a few moderately long reddish hairs, variable in size. Mandibles 

 very long, falciform, each with a large angular tooth before the middle (fig. 5). 

 Labrum large, wide at the base, sloping on the sides to the bluntly pointed apex. 

 Clypeus three times as wide as long, divided into two lobes by a deep and wide median 

 cleft, which extends posteriorly into the front of the head. Antennae 17- or 

 18-jointed, generally segmented as in D. rubriccps, Frogg., sometimes third and 

 fourth joints closely fused and together only equal to sixth in length. 



Prothorax (fig. 4) much narrower than head, anterior half rounded and bent up 

 in front, slightly emarginate in middle, postero-lateral angles rounded, hind margin 

 rounded and shghtly emarginate in middle ; the margin clothed with short stout 

 reddish hairs. Mesothorax narrower and shorter than prothorax, hind margin with 

 a few stout reddish hairs. Metathorax as wide as prothorax and clothed like meso- 

 thorax. Legs very long and slender, with scattered reddish hairs, fourth tarsal verj' 

 long. Tibial spurs 3 : 2 : 2, as in other Drcpanotennes and Hamitermes. 



Abdomen elongate, narrow, with scattered stout reddish hairs and a few slender 

 golden ones on tergites and sternites. Cerci long and slender. Styli present or absent. 



Fig. 5. Drepanotermes silvestrii, sp. n., 

 base of jaws, labrum and clypeus of 

 soldier. 



Measurements: Total length, 6-25-7; head and mandibles, 2 •75-3-1 long; 

 thorax and abdomen, 4-4-5 long; mandibles, 1-31-1-64 long; head, 1-6 wide; 

 1-25-1-35 deep; antennae, 3-29-3-61; prothorax, 0-51-0-56 long, 1-03-1-12 

 wide ; tibia (i) 1-5, (ii) 1-5, (iii) 2- 11-2-39 ; abdomen, 1 -5 wide. 



Worker. — Colour of head as in soldier, or a little darker, with pale median suture 

 extending forwards from the posterior margin, widening behind the fontanelle and 

 spreading out behind the frons ; clypeus clay-colour, labrum yellow-ochre ; antennae 

 a little paler ; rest of insect clay-colour ; prothorax a little darker than tergites and 

 legs. Immature workers and soldiers have body and legs tinged with rose pink. 



Head large, rounded on the sides and behind, nearly as wide as long, widest behind 

 the base of the mandibles. Labrum large, convex, swollen on the sides, rounded in 

 front. Anteclypeus membranous, short, pointed. Postclypeus large, convex at base, 

 not quite as long as wide, sides rounded, anterior margin truncate. Antennae 

 very long, 18-jointed, arising within a deep cleft situated well in from sides of head. 

 Fontanelle as in imago. 



Prothorax as in soldier, more setose, much narrower than head. Legs long and 

 slender, clothed with scattered reddish hairs. Tibial spurs 3:2:2. 



Abdomen elongate oval, hairs more numerous and more slender than in soldier. 

 Cerci long and slender. 



Measurements: Total length, 7-7-5; head, with mandibles, 2-16-2-35 long; 

 thorax and abdomen, 5-5 long ; head, 1 -93 wide ; antennae, 3-61 ; prothorax, 0-56- 

 • 6 long, 1 - 22 wide ; mandibles, left, - 97 long, - 65 wide, right, - 86 long, - 77 wide. 



