THE SOLDIERLESS TERMITES OF AFRICA 77 



to second pouch of proctodeum by distinct neck; membranous wall of valve beyond cushions 

 with sparse minute spicules. 



Measurements (one specimen) in millimetres. 



Head width (W) .... 085 

 Fore tibia width (T w ) . . . .012 



Fore tibia length (Ti) .... 063 



Postclypeus length (Pel) . . . 0-22 



Left mandible, apical to first marginal (L A ) 008 



Left mandible, first to third marginal (Li) . 0-13 

 Left mandible, third marginal to molar 



(L m ) 006 



Right mandible, apical to first marginal 



(Ra) 0-08 



Right mandible, first to second marginal 



(Ri) 009 



Right mandible, second marginal to molar 



(R11.) 006 



This species, with A. murcus, is characterized by the very long head setae of the 

 imago which separate these two from the rest of Group II. A. murcus differs from 

 A. ignavus in having a slightly more evenly rounded head capsule and narrower 

 meso- and metanota. The worker of A . murcus has the first marginal tooth of the 

 right mandible somewhat reduced compared with that of A. ignavus. The vestigial 

 third spur of the worker fore tibia distinguishes these two species from others of 

 Group II apart from A. mitis, but this has a thicker fore tibia, more inflated post- 

 clypeus, and longer apical teeth to the mandibles. A. irrixosus which also has a 

 vestigial third tibial spur is much larger, with longer apical teeth, and a very wide 

 notch separating the subsidiary marginal tooth of the left mandible from its molar 

 prominence. Other comparative details are given in the discussion of species 

 already described. One in four specimens of the worker caste of A. ignavus shows 

 abdominal dehiscence. 



Holotype queen, paratype king and workers from type-colony, Congo (Brazza- 

 ville): 13 km W. of Brazzaville, 8.vi.icj48 (A. E. Emerson) in American Museum 

 of Natural History. (Paratype second queen and workers from type-colony, also 

 in BMNH.) 



The only known nest-series was collected at the base of a dead stump in an open 

 field. 



Astalotermes mitis sp. n. 



(Text-figs 112, 113, 122, 123 & 144-149) 



Imago. Head capsule sepia-brown, not darker above ocelli; fontanelle small, less than half 

 as long as ocellus, very short oval, somewhat depressed in middle with slight transverse striations, 

 pale yellow-biown; medial spot circular, fiat, smaller than fontanelle, sepia-brown; postclypeus 

 brown, labrum yellow-brown; frontal marks fiat, crescent-shaped, brown; antennae yellow- 

 brown, pronotum brown, meso- and metanota, yellow-brown; only the latter with transverse 

 dark suture; legs, femora yellow-brown, tibiae paler, tarsi yellow. Abdominal tergites and 



