SMITH ON HYMENOPTERA Or ARTJ ISLANDS. 137 



6. Formica cordata. F. pallida rufa; abdornine fusco, capite cor- 

 date. 



Worker. Length 2 lines. Pale rufo-testaceous ; the head heart-shaped ; 

 the eyes black, the flagellura fusco-ferruginous with the basal joints 

 pale ; the mandibles ferruginous. Thorax narrow, deeply strangulated 

 at the base of the metathorax. Abdomen more or less fuscous, the 

 node of the petiole narrow and pointed above ; the entire insect is 

 smooth and shining. 



Hub. Aru. 



The worker minor is rather smaller and has the abdomen darker, in all 



the specimens received, but in other respects agrees with the above. 



7. Formica oculata. F. pallide ferruginea; capite oblongo, oculis 

 magnis, thorace compresso. 



Worker. Length 2^ lines. Pale ferruginous, with the vertex and apex 

 of the abdomen black ; the head oblong, the sides nearly parallel, with 

 the anterior margin truncate ; the mandibles with fine acute teeth on 

 their inner margin ; the antennae inserted wide apart about the middle 

 of the head ; the eyes very large and ovate, placed backwards on the 

 sides of. the head, reaching to the posterior margin of the vertex, 

 forming as it were its posterior lateral angles. The thorax narrow 

 and compressed behind ; abdomen ovate, entirely smooth and shining. 



Hab. Aru. 



8. Formica MUTiLATA. F. nigra ; capite oblongo, truncate antice et 

 sanguineo, antennis tarsisque rufo-testaceis. 



Worker. Length 2f lines. Black and shining ; the head truncate an- 

 teriorly, the antennae inserted wide apart, about the middle, the face 

 blood-red before their insertion and deeply striated longitudinally, 

 behind the antennae the head is black, smooth, and shining ; the eyes 

 ovate and placed backwards on the sides of the head. Thorax 

 rounded in front and strangulated between the meso- and metathorax, 

 the latter obliquely truncate ; legs rather short and stout, the femora 

 compressed, the anterior pair broadly dilated, the base and apex of 

 the femora, the tibiae, and tarsi rufo-testaceous, the tibiae with a darker 

 stain behind. Abdomen oblong-ovate, the apical margins of the seg- 

 ments narrowly pale testaceous ; the scale of the petiole compressed, 

 with its superior margin rounded. 



Hab. Aru. 



This is a very singular insect in many respects, and closely resembles 



in form the Formica truncaia of Spinola. 



9. Formica quadriceps. F. nigra, nitida; capite antice oblique 

 truncate, thorace postice compresso. 



Worker. Length 3^ lines. Shining black; head oblong-quadrate, 

 slightly narrowed anteriorly, wdth the sides nearly straight, the pos- 

 terior angles rounded, and very slightly emarginate behind ; the head 

 obliquely truncate from the base of the clypeus ; the truncation as 



