348 bulletin: museum of comparative zoology. 



75. Tetramorium tonganum Mayr. 



Verh. K. K. zool.-bot. gesellsch. Wien., 1870, 20, p. 972, 976, y . 

 SanCristoval: Wainoni Bay. Guadalacanar: Aula. 



76a. XiPHOMYRMEx costatus Emery, subsp. flavescens Emery. 



Term, fuzet., 1897, 20, p. 588, ^ . 

 Male. Length 3 mm. 



Head, excluding eyes, longer than broad; occipital border straight, the 

 angles broadly rounded. Mandibles similar to those of worker, with strong 

 apical and subapical teeth. Clypeus convex, carinate at middle, broadly 

 rounded in front. Eyes very large and convex, located at a distance equal to 

 one fifth their length from bases of mandibles; ocelli large. Antennae slender, 

 10-jointed, their scapes surpassing occipital corners; first funicular joint one 

 and one half times as long as broad, second joint longer than the third and 

 fourth together, joints three to eight subequal, cyhndrical; terminal joint one 

 and one half times as long as penultimate. Mesonotum rather flat at apical 

 half, without Mayiian furrows. Scutellum transverse, httle convex above. 

 Epinotum deeply transversely grooved at base; the rest flat, narrowly mar- 

 gined at sides. Petiole long and slender; petiole as long as node, flattened 

 above and narrowly margined at sides; node longer than high; from above 

 longer than broad, transversely impressed apical ly Postpetiole rounded, 

 broader than long. Legs long and slender. 



Shining, petiole, postpetiole, and gaster more so than the rest. Mandibles 

 finely strigose. Clypeus with two lateral carinae which are much stronger 

 than the median one. Head, thorax, and epinotum with reticulate carinae. 

 Petiole, postpetiole, and gaster smooth. Legs finely and rather densely, 

 though shallowly punctate. Antennal scapes finely, funiculus rugosely punc- 

 tate. 



With sparse, scattered, semicircumbent hairs throughout. Color testaceous; 

 funiculus, tibiae, and tarsi fuscous. Wings hyaline; veins and stigma fuscous. 



Bio. Three Sisters : Malapaina. San Cristoval: Pamua. Malaita: 

 Auki, Interior of. Florida: Tulagi. Russell: West Bay. Ysabel: 

 Fulakora. 



The form that I refer to this subspecies is common in the forests, 

 where workers are frequently seen on tree-trunks and leaves. The 

 colonies are small and live in hollow twigs (in most instances rotten 

 ones), beneath bark and more rarely in the ground. 



