430 bulletin: MUSEUM 01 COMPARATIVE ZO#LOGY. 



A distind Bpecies, characterized bj the structure of the mesonotum 

 in the soldier ami l>\ the elei ated triangular project ions at sides of the 

 pro- and mesonotuin in worker. 



The colonies found vrerc small ones, situated beneath stones. Type, 

 — M.C.Z. 8,694, 



22. Pheidole umbonata Mayr. 



Sitz. Akad. wiss. Wien, L866, 53, p. 510, 3 o* (excl. 9 01). Verh. Zool. bot. 

 geseltech. Wien, L870, 20, p. 977, 978, °j. 



Soldier. Length 2.10 2.60 mm. 



Head a little longer than broad, as broad in front as behind, sides moder- 

 ately convex, occipital border broadly and, at middle, rather deeply excised, 

 vertex not transversely impressed. Mandibles with a tooth at the angle 

 between base and blade, bidentate at tip. Clypeus flat in front, its anterior 

 border nearly straight. Antennal scapes extending a little less than half the 

 distance to occipital corners; first funicular joint as long as the next three 

 joints together, joints 2-8 a little broader than long; club shorter than re- 

 mainder of funiculus, its terminal joint longer than the other two together. 

 Eyes little convex, situated at anterior fourth of head. Pronotum much 

 broader than long, sides submargincd and broadly rounded at tips. Pro- 

 mesonotal suture barely distinct. Mesonotuin flat. Epinotum shallow ly 

 concave between the spines, the base about as long as declivity; -puns triangu- 

 lar and acute, shorter than their distance apart at base. Petiole rather short, 

 node in profile; higher than long; above, concave at middle with the sides 

 subcorneal. Postpetiole a little less than twice as broad as petiole, broader 

 than 1mm, broadest in front of middle, with nearly straight sides. 



Moderately shining throughout. Mandibles with fine and regular setiger- 

 ous punctures. Head regularly, longitudinally striate, the striae becoming 

 obsolete on vertex; occiput smooth. Pro- and mesonotuin smooth. Epino- 

 tum coarsely, though shallow ly reticulate. Petiole, postpetiole, and gaster 

 smooth. 



Fine, erect hairs moderately abundant on head, body, and appendages. 



Brownish yellow, gaster pale fuscous. 



Worker. Length 1.25-1.50 mm. 



Head slightly longer than broad, sides feebly convex, posterior corners 

 broadly rounded, occipital border very shallowly concave at middle. Mandi- 

 bles with fine elongate triangulate teeth. Clypeus straight at anterior border. 

 Antennal scapes slightly surpassing occipital corners; funicular joints 2-8 

 about as long as broad. Eyes large, situated at anterior third of sides of head. 

 Pronotum evenly rounded above and at sides. Promesonotal suture very 



