162 FOBMICLD^E. 



workers is far more ferocious and effective than that of the soldiers. 

 As for the giants, they are useless as fighters, and beyond occasion- 

 ally acting as " state elephants," as Mr. Aitken has somewhere 

 humorously suggested, they appear, so far as I could see, to be of 

 no use to the community. Mr. Rothney, however, records having 

 seen them on one of their covered ways " very busy not carrying 

 or building-up, but slowly making their way along the line, and 

 here and there stopping and rearing themselves up against the 

 walls, pressing together and smoothing out in a way that their 

 great size gave them special facility for doing ;" so after all they 

 may be the trowels and rammers of the Ants' Public "Works 

 Department. 



Key to the Species. 



3/1/. 

 . Length 4'5-13 mm. 



a'. Front of the head bearing a single ocellus in 



the middle P. diversus, p. 162. 



b' . Front without any ocellus P. affinis, p. 164. 



b. Length under 4'5 mm P. nanus, p. 165. 



$ $. 



a. Colour dark chestnut-brown ; length over 2'5 mm. P. diversus, p. 162. 



b. Colour light brownish yellow ; length under 



2'5 mm. 



'. Length 2-2'5 mm. Sides of the head smooth. P. affinis, p. 164. 

 b'. Length barely 2 mm. Sides of the head 



finely rugose P. nanus *, p. 165. 



187. Phidologiton diversus, Jerdon (Ocodoma), Madr. Jour. L. S. 



xvii (1851), p. 109, . 



Pheidole ocellifera & taprobanse, Smith, Cat. vi (1858), pp. 174, . 

 & 175, $ . 



%max. Dark chestnut-brown; mandibles nearly black ; antennae 

 and legs more or less reddish brown ; head anteriorly and thorax 



on the sides longitudinally 

 striate, the posterior lobes 

 of the head in front, the 

 pronotum anteriorly and 

 the basal portion of the 

 metanotum transversely 

 striate ; the 1st node of the 

 pedicel irregularly rugose, 

 the rest of the insect smooth, 

 Kg. Go.-Phidoloffiton diversus, y. shining and polished. Head 



rectangular, as broad in 



front as posteriorly, the sides straight, the posterior border widely 

 emarginate, a deeply impressed medial narrow groove down the 

 front, with a single large ocellus at the beginning of its lower third ; 

 mandibles large, nearly black, smooth, with a few shallow punctures, 



* P. lamellifrons, Forel, p. 166, is not included in the key, only the $ being 

 known. 



