A Monograph of the Formicidae of South Afr'ika. 609 



towards the apex of the latter. Petiole long, linear, scarcely, thick- 

 ened at all; abdomen depressed, oval; external genitalia large." 



I have not seen the cfcf of this genus, and the generic characters 

 quoted above are taken from Binghams "Ants of India". 



Distribution. Tropics of the Eastern Hemisphere. 



0. smaragdina, Fabr., (Plate IX, figs. 134, 134a). 



Syst. Ent. p. 828, Q. 1775, 



Guerin, (Formica macro) Voyage Goquille, Zool. II, p. 202, §. 1830. 



Jerdon, Madras Jour. Litt. Sc. Vol. 17, p. 121, & $, cf. 1851. 



^, 7-11 mm. Yellowish (buff) red, the abdomen similar but with 

 a brownish tinge as well, the apical margins of the segments paler 

 and translucent. Pubescence short, decumbent, pale yellowish, fairly 

 abundant all over; pilose hairs thin, present only on the anterior 

 margin of the clypeus and the apical margins of the abdominal seg- 

 ments. Exceedingly finely rugulose and dull all over. 



Head, including the closed mandibles, subtriangular with the angles 

 rounded, widest behind, the posterior margin straight, the sides 

 moderately convex, high in the middle and strongly convex from 

 side to side. Mandibles closely striolate, the teeth black. Clypeus 

 half as long as wide, raised towards the middle, the anterior margin 

 convex. The scape, strongly incrassate near the apex, extends beyond 

 the hind margin of the head by two-thirds of its length. All the 

 joints of the flagellum longer than wide and decreasing in length 

 progressively from the 1st to the penultimate joint. Pronotum nar- 

 rower than the head, and including the neck-like portion longer than 

 wide. Mesonotum narrowed a little behind, about as long as wide 

 in front. Metanotum short in the middle, convex and considerably 

 constricted in front, convex and much longer at the sides, in such 

 a way as to embrace the anterior part of the epinotum ; metanotal 

 stigmata large and prominent. Epinotum very convex lengthwise, 

 the dorsum about as long as the declivity. Petiole widening and 

 rising gradually from its base to the posterior fourth, where it be- 

 comes slightly constricted and inclined downwards, produced on each 

 side into a small (lap embracing the articulation of the abdomen. 



Abdomen oval or subcircular. Legs very long, the posterior femora 

 as long as, or a little longer than the tibiae. 



"Q, 15-18 mm. Characters of the genus. Normally of a beautiful 

 emerald-green, with a peculiar pellucid translucent appearance when 

 alive. Varieties arc found of a pale yellow, with more or less brownish 



