194 w - A - SANDS 



2 Small, W, 0-65-0-69. Apical teeth of mandibles longer, L A /Li, 0-67-0-76, R A /Ri, 



0-84-1-00. Postclypeus more inflated, Pcl/W, 0-29-0-32. Fontanelle very small 



and indistinct, little paler than head ...... nanus (p. 215) 



- Larger, W, o-8o. Apical teeth of mandibles shorter, La/Li, 054, R A /Ri, o-68. 



Postclypeus less inflated, Pcl/W, 0-26. Fontanelle more conspicuous, pale, 

 contrasting with head colour ..... ateuchestes (p. 198) 



3 Meso- and metanota proportionately wider at constriction, M/W, 0-28-0-31. Right 



mandible with anterior edge of first marginal tooth distinctly longer than that 



of second ......... improelatans (p. 212) 



- Meso- and metanota proportionately narrower at constriction, M/W, o- 19-0-26. 



Right mandible with anterior edges of first and second marginals equal . . 4 



4 Postclypeus less inflated, Pcl/W, 0-25-0-26 ....... 5 



- Postclypeus more inflated, Pcl/W, 0-28-0-34 ....... 7 



5 Smaller, W, 0-69-0-79 ....... polyscolus (p. 217) 



- Larger, W, 087-1 06 ........... 6 



6 Larger, W, 0-99-1-06. Postclypeus with sinuate posterior margin and distinct 



median suture ......... hemerus (p. 209) 



- Smaller, W, 0-87-0-94. Postclypeus with more or less evenly rounded but indistinct 



posterior margin, median suture very indistinct or absent . . cicur (p. 200) 



7 Posterior margin of head capsule behind eyes evenly rounded .... 8 



- Posterior margin of head capsule behind eyes unevenly rounded, slightly undulating 



amachetus (p. 195) 



8 Smaller, W, 0-69-0-79 ........... 9 



- Larger, W, 0-84-0-96 ........... 10 



9 Fontanelle minute, vestigial, only slightly paler than head. Pilosity of head capsule 



dense, uneven, not forming a pelt. Postclypeus generally more inflated, Pcl/W, 

 0-30-0-34 .......... improcinctus (p. 212) 



- Fontanelle large, often approaching size of ocelli, usually distinctly paler than 



head but still visible even when coloured as head. Pilosity often even, forming 

 a pelt with emergent setae. Postclypeus less inflated, Pcl/W, 0-23-0-31 



polyscolus (p. 217) 

 10 Apical teeth of mandibles longer, L A /Li, 0-60-0-64, R A /Ri, 0-83-0-89. (Complex 

 ratios give clearer separation, L A /Li.Ln,, 9-93-10-10, Ri/R A R m , 17-3-19-4) 



cnaphorus (p 203) 



- Apical teeth of mandibles shorter, L A /Li, 0-46-0-56, R A /Ri, 0-62-0-75 (L A /Li.L m , 



6-76-8-51, Ri/R A .R m , 22-0-28-5) ..... . disluctans (p. 206) 



Workers 



1 Enteric valve cushions armed with distinct spines at their distal ends ... 2 



- Enteric valve cushions not so armed ......... 4 



2 Enteric valve cushions in position 3 elongated, protruding through valve opening, 



armed with a fringe of long pectinate spines, other cushions short, with small 

 spines ............. 3 



- Enteric valve cushions not elongated or protruding through valve opening, armed 



with small spines . ......... nanus (p. 215) 



3 Enteric valve cushions of position 3 shorter and broader as in PI. 8, fig. 3. Larger, 



W, 0-72-0-73. Apical teeth of mandibles longer, L A /Lj, 0-64-0-66, R A /Ri, 

 0-84-0-89 .......... cnaphorus (p. 203) 



- Enteric valve cushions of position 3 longer and narrower as in PI. 8, figs 4-6. Smaller 



W, 0-60-0-64. Apical teeth of mandibles shorter, L A /Li, 0-50-0-60, R A /Ri, 

 0-68-0-80 .......... polyscolus (p. 217) 



4 Right mandible with anterior edges of first and second marginal teeth equal in 



length. Mixed segment with proctodeal overlap relatively short, length less 



