wheeler: the ants of Borneo. 45 



epinotum (siibgen. Physocrema) than occur in other regions. Lepto- 

 genys is represented by several large and handsome species of the 

 subgenus Lobopelta, and Cataulacus, Dolichoderus (subgen. Hypo- 

 clinea), Polyrhachis, and Echinopla are also rich in species. All but 

 three of the subgenera of Polyrhachis (Hagiomyrma, Hedomj^ma, 

 and Myrmatopa) are known to occur in the island. Of Camponotus 

 the subgenera Myrmotarsus and Colobopsis are represented by 

 numerous species, while most of the other subgenera are rather poorly 

 represented, though often by peculiar forms (Myrmoturba, Myrmo- 

 sphincta). Compared with the Philippines and the adjacent main- 

 land, and especially with Papua and Australia, Borneo seems to possess 

 few species of Pheidole and Monomorium, and many primitive poner- 

 ine genera have not been recorded from the island, e.g. Mystrium, 

 Stigmatomma, Trapeziopelta, Prodiscothyrea, Cryptopone, and 

 Centromyrmex. I believe, however, that some or all of these will 

 be foimd in Borneo. Only recently I received species of Mystrium, 

 Stigmatomma, Trapeziopelta, and Centromyrmex from the Phil- 

 ippines, where they were previously unknown. Of course, Borneo 

 has been invaded by the usual tropicopolitan tramp species, Mono- 

 morium pharaonis and floricola, Telraviorium guineense and similli- 

 mum, Pheidole viegacephala, Triglyphothrix striatidens, Plagiolepis 

 longipes, and Prenolepis longicornis, and obscura.. 



FORMICIDAE : PONERINAE. 



1. Cerapachys antennatus Smith. 



Cerapachys antennatus Smith, Journ. Proc. Linn. soc. London. Zool., 1857, 2, 

 p. 74, y ; Emery, Ann. Mus. civ. Genova, 1887, ser. 2, 5, p. 445, 9, pi. 1, 

 fig. 8, 9; Emery, Gen. Ins. Ponerinae, 1911, p. 9, S 9. 



Type-locality: Sarawak, Borneo (A. R. Wallace). 

 Worker. Length 5.5 mm. 



Head distinctly longer than broad, narrower in front, than behind, with 

 straight sides, broadly concave occipital border, acute occipital angles and 

 convex dorsal surface, subtruncate behind. Eyes rather large, flattened, 

 their anterior orbits at the middle of the head. There is a small shallow 

 impression on the middle of the vertex. Occipital border marginate, the 

 margination surrounding the corners and continued some distance along the 

 ventral surface of the head. Gula with a pair of small, prominent teeth at 



