50 bulletin: museum of comparative zoology. 



Onychomyrmex hedleyi Emery. 



Plate 1, fig. 1, 2. 



Emery, Ann. Soe. ent. Belg., 39, 1895, p. 350, f. 2. ^ ; Gen. 

 Insect., 1911, fasc. 118, p. 97, pi. 3, f. 9, 9b; Forel, Arkiv. f. zool., 

 1915, 9, p. 3, pi. 1, f. 3 ^ cf (?). 



Worker. Length 3.5-4 mm. 



Head about I5 times as long as broad, subreetangular, a little 

 broader in front than behind, with straight sides and posterior border 

 and rounded posterior corners. Clypeus with the anterior border 

 slightly flattened, arcuately rounded in the middle, sinuate at the sides, 

 its edge beset with about 20 minute, regular teeth. Eyes with about 

 6-8 minute ommatidia, situated | the length of the head from the 

 anterior margin. Mandibles with long, abruptly incurved apical 

 tooth and seven basal teeth of different sizes, the two in the middle 

 of the series largest and directed backward. Antennae slender, 

 scapes fully | as long as the head, first and last funicular joints twice 

 as long as broad, remaining joints about I2 times as long as broad. 

 Thoracic sutures all strongly impressed; pronotum convex above, 

 especially in front, with convex sides, a little longer than broad; 

 mesonotum nearly twice as broad as long ; epinotum longer and nar- 

 rower than the pronotum, longer than broad, Avith feebly convex sides 

 and separated in dorsal view from the pronotum by a pronounced 

 impression on each side. In profile the thorax is distinctly impressed 

 at the mesonotum, the base of the epinotum is nearly twice as long 

 as the straight declivity into which it passes through an obtuse 

 angle. Node of petiole in profile with rather straight anterior slope 

 and convex summit, slightly concave at the posterior border; from 

 above the node is as long as broad, rounded in front, with straight 

 posterior border; ventral projection long and blunt, compressed and 

 somewhat translucent. Postpetiole as long as broad, first gastric 

 segment a little longer than the postpetiole. Legs slender. 



Very smooth and shining; mandibles, clypeus, and cheeks sub- 

 opaque, the mandibles finely striated, the cl.A'peus and cheeks finely 

 rugulose-punctate. Bodj- with fine, sparse, piligerous punctures, 

 which are most numerous on the head, especially on its sides. 



Hairs delicate, pale yellowish, short, suberect, covering not only 

 the whole body, legs, and antennal scapes but also the funiculi; 



