HYMENOPTERA. 65 



25. POLYRHACHIS BICOLOR. B.M. 



Female. Length 3^ lines. Head, thorax and scale of the 

 abdomen black ; antennae, mandibles, palpi, legs and abdomen 

 rufo-castaneous. Head covered with short cinereous pubescence ; 

 the frontal carinae, at the sides of which the antennae are inserted, 

 much elevated ; the eyes and ocelli reddish. Thorax ovate, and, 

 as well as the scale of the peduncle, covered with short cinereous 

 pubescence ; the prothorax with a short acute spine on each side ; 

 there is also a similar spine on each side of the metathorax ; the 

 posterior tibiae and tarsi fuscous. Abdomen globose, thinly 

 covered with fine cinereous pile ; the scale of the peduncle in- 

 crassate, quadrate, and with an acute spine at each of the superior 

 angles, the spines straight and divergent. 

 Hab. Burmah. 



26. POLYRHACHIS SUMATRENSIS. PI. IV. fig. 43. B.M. 



Female. Length 4-J lines. Head and thorax opake-black ; 

 abdomen slightly shining and pubescent. Head narrowed behind 

 the eyes, which are ovate and prominent ; in front of the eyes 

 oblong-quadrate, with the anterior margin of the clypeus rounded. 

 Thorax oblong-ovate, with the metathorax truncated, the verge 

 of the truncation margined; the prothorax with an acute spine 

 on each side ; wings fusco-hyaline, the nervures testaceous, the 

 stigma and costal nervure brown ; the legs slightly pubescent. 

 Abdomen subglobose; the scale of the peduncle incrassate, 

 rounded in front and slightly convex behind ; viewed in front 

 somewhat quadrate, but widest above, the superior margin with 

 the lateral angles produced into short acute teeth, the middle of 

 the margin subdentate ; there is also a short acute spine on each 

 side beneath the lateral angles. 

 Hab. Sumatra. 



27- POLYRHACHIS PANDARUS. PL IV. fig. 45. B.M. 



Worker. Length 4 lines. Black : head and thorax coarsely 

 shagreened ; the palpi pale testaceous ; head below the antennae 

 finely shagreened; the posterior margin sharply recurved. Thorax 

 not flattened above ; two long, stout, acute, divergent spines in 

 front, and two similar ones behind ; the scale quadrate, with two 

 long, acute, divergent spines directed backwards ; legs without 

 spines or hairs ; the anterior tibiae with their calcaria pale tes- 

 taceous, those on the intermediate and posterior legs black. Ab- 

 domen smooth, opake-black. 



Hab. Borneo (Sarawak). 



Specimens from Singapore have the abdomen rusty-red. 



