5<o ANTS. 



Tropical and subtropical species with very slender thorax and le^. 



Subgcn. Ischnomyrmex Mayr. 



26. Clypeus armed with a pair of ridges which project forward in the form of 



teeth, rarelv without teeth, but then the cpinotum is quite unarmed; meso- 



epinota! suture marked Monomorium Mayr. 



Clypeus of a ditTereiit conformation; rarely 2-toothed, but then the mesoepi- 

 notal suture is indistinct 27. 



27. Postpetiole campanulate, not constricted behind but applied with its whole 



posterior surface to the first gastric segment Macromischa Roger. 



Postpetiole constricted behind Leptothorax Mayr. 



Subfamily DOLICHODEKIN.E. 



i. Chitinous integument hard and brittle, declivity of epinotum strongly concave. 



Dolichoderus Lund; subgen. Hypoclinea Mayr. 

 Chitinous integument thin and flexible, smooth or very finely sculptured, 



declivity of epinotum not strongly concave 2. 



_. Scale of petiole very small, strongly inclined forward, or even altogether 



absent 3. 



Scale of petiole more or less inclined but well-developed 4. 



3. Scale of petiole small but indistinct ; gizzard with a convex, 4-lobed calyx. 



Forclius Emery. 

 Scale vestigial or absent; gizzard with a depressed calyx, without lobes. 



Tapinoma Foerster. 



4. Epinotum with a conical elevation Dorymyrmex Mayr. 



Epinotum without a conical elevation 5. 



5. Body not conspicuously hairy or pubescent; gizzard very short, with a large 



reflected calyx ; ocelli absent Iridomyrmex Mayr. 



Body densely pubescent ; gizzard at least as long as broad ; ocelli usually 

 present in large workers Liometopum Mayr. 



Subfamily CAMPONOTIN^:. 



1. Antennae g-jointed Brachymynncx Mayr. 



Antennae with more than 9 joints 2. 



2. Workers di- or polymorphic 3- 



Workers not polymorphic though often of variable size 4. 



3. Workers polymorphic, /. e., with forms (mediae) intermediate between the 



largest and smallest workers ; head of largest workers not sharply trun- 

 cated anteriorly Camponotus Mayr. s. str. 



Workers dimorphic, /. e., without intermediate forms; head of largest 

 workers sharply truncated anteriorly Subgen. Colobopsis Mayr. 



4. Clypeal fossa distinctly separated from the antennal fossa 5. 



Clypeal fossa confluent with the antennal fossa 6. 



5. Antennal scapes and tibiae without erect hairs ; mesonotum strongly con- 



stricted and sub9ylindrical Prcnolcpis Mayr. s. str. 



Antennal scapes and tibiae with erect hairs ; mesonotum constricted but not 

 subcylindrical Subgen. Nylandcria Emery. 



6. Joints 2-5 of the funiculus shorter or not longer than the succeeding joints; 



ocelli usually absent 7- 



Joints 2-5 of the funiculus longer than the succeeding joints; ocelli dis- 

 tinct 8. 



7. Maxillary palpi 6-jointed Lasiits Fabr. s. str. 



Maxillary palpi 3-jointed Subgen. Acanthomyops Mayr. 



8. Fourth joint of maxillary palpi nearly as long as the fifth. 



Myrmccocystus Wesmael. 



Fourth joint of maxillary palpi a little longer than the fifth 9. 



Q. Mandibles with broad, dentate, masticatory border Formica Linn. 



Mandibles narrow, falcate and pointed Polycrgus Latreille. 



