THE SOLDIERLESS TERMITES OF AFRICA 81 



Antennal article IV 006-008 



Antennal article V . . . 006-007 



Left mandible, apical to first mar- 

 ginal (L A ) .... 009-0- 10 



Left mandible, first to third mar- 

 ginal (Li) .... 016-018 



Left mandible, third marginal to 



molar (L m ) .... 008-009 



Right mandible, apical to first 



marginal (Ra) .... 009-010 



Right mandible, first to second 



marginal (Rj) .... 0-11-0-13 



Right mandible, second marginal 



to molar (R m ) • • • 009 



Mesonotum width (M) . . . 0-30-0-32 



Metanotum width (N) . . . 0-28-0-34 



Worker. Head capsule pale yellow, pilosity yellow, long, numerous and conspicuous. 

 Postclypeus moderately inflated, Pcl/W, 030, Pcl/R|, 263; apical teeth of mandibles short, 

 La/Lj, 064, R A /Ri, 085; subsidiary marginal tooth of left mandible separated from molar 

 prominence by distinct notch in surface view, complex ratio La/Li. L m , 790; first marginal tooth 

 of right mandible slightly behind line of apical to second marginal, its anterior margin distinctly 

 shorter than that of second, R A /R| R m . 10-46. Fore tibia slender, Ti/T Wl 5-80, third apical 

 spur vestigial. Mesenteric junction with proctodeum diagonal, touching malpighian knot 

 on right; enteric valve seating lateral in unopened abdomen, weakly bilobed, connected to 

 second pouch of proctodeum by long neck; membranous wall of valve beyond cushions with 

 sparse minute spicules. 



Measurements (one specimen) in millimetres. 



Head width (W) . . . . 103 



Fore tibia width (T w ) . . . . 014 



Fore tibia length (T|) .... o-8i 



Postclypeus length (Pel) . . . 03 1 



Left mandible, apical to first marginal (La) o-io 



Left mandible, first to third marginal (Li) . 0-16 

 Left mandible, third marginal to molar 



(L m ) 0-08 



Right mandible, apical to first marginal 



(Ra) 010 



Right mandible, first to second marginal 



(Ri) 012 



Right mandible, second marginal to molar 



(Rm) 008 



Comparisons of A. murcus with Group II species have been made in the preceding 

 descriptions. Its very close similarity to A. ignavus gave rise to some uncertainty 

 as to whether these two should be described separately or considered one species. 

 However, the two records are from over 1,000 miles apart. The differences in the 

 proportions of the mandibles, and the meso- and metanotal constrictions are such 

 as are found between species or even genera that are clearly separated by other 

 characters; they are also found within a single variable species. The decision to 

 split them in the absence of intermediate specimens was taken on the principle 

 that this will cause less confusion in the long run than the converse should either 



