ERIC MJÖBERG, ISOPTERA. 87 



projecting median tooth, which, however, is not quite so 

 sharp; antenna? 15-jointed, the 3rd joint quite free (in H. 

 oheuntis Silv. coalescing with 4th), 6th to 14th much longer 

 than broad, 15th narrow, more than twice as long as broad, 

 tapering to the tip; prothorax ridged in front, rounded at 

 the sides, hairy; legs long, hairy; abdomen very broad and 

 rounded, of the same shape as in the soldier of H. Harimeyeri 

 Silv. (see Silvestri's fig. 147, Taf. XX in »Die Fauna Siid- 

 west-Australiens, Bd II, Tsoptera), cerci long. 



Measurements: Length of body with jaws 5 mm, length 

 of head with jaws 2, o 7 mm, length of head without jaws 1,6 5 

 mm, breadth of head 1,29 mm, length of prothorax 0,42 mm, 

 breadth of prothorax 0,74 mm, breadth of abdomen 1,5 mm. 



Work er. Elongate, whitish— light yellowish, head light 

 reddish yellow. 



Head rounded, flattened on the summit; basal part of 

 clypeus more than twice as long as broad, rounded on the 

 sides, apical part whitish, protruding in the middle; labrum 

 broad and rounded at the tip; jaws broad and stout, with a 

 dentition very similar to the one in H. ohtusidens Mjöb., 

 antennse 15-jointed, 3rd joint either undivided or incomple- 

 tely divided into two very short parts, 14th and 15th joint 

 fully twice as long as broad; prothorax ridged, rounded; 

 abdomen elongate, rounded. 



Measurements: Length of body 5 mm, length of head 

 1,3 7 mm, breadth of head l,i8 mm, length of prothorax 

 0,49 mm, breadth of prothorax 0,7 1 mm, breadth of abdomen 

 1,6 mm. 



The species is in many respects closely allied to H. 

 obiusidens Mjöb.; the imagines at first sight look quite 

 similar, but prove to be quite distinct from each other at 

 closer examination. The fontanelle is broader and more 

 rounded and the apical joints of antennse constantjy different 

 (see description); also in regard to the wings they are dif- 

 ferent. The soldier is very like the soldier of H. oheuntis 

 Silv. but differs in the shape of the jaws and labrum and 

 also in the joints of antennse. 



It lives under stones on the ground making very simple 

 earthy galleries. Numerous winged insects, one soldier and 

 many workers taken in November at Christmas Creek in 

 Southern Queensland. 



