26 ENTOMOLOGICAL SOCIETY 



Gattung Dorylus Fabr., und systematische Eintheilung der 

 Formiciden/' a has done a great work in unraveling the con 

 fusion that existed in regard to the genera and species, and has 

 formed the basis of this table: 



TABLE OF GENERA. 



1. Workers 2. 



Females 14 



Males 17 



2. Pro-mesonotal suture always more or less distinct ; mesonotal su 



ture dorsally wanting or obsolete; pygidium usually tridentate; 



metathoracic spiracles alone distinct 3 



Pro-mesonotal suture obsolete; if the mesonotal suture is distinct 



it is due to remarkable polymorphism 9 



3. Head in large individuals longer than wide 4 



Head, in large individuals, wider than long; mandibles long sickle- 

 shaped, with a large tooth within at the middle; in small indi 

 viduals with a prominent clypeus; antennae u -jointed, 



Anomma Shuckard 

 (Type, A. burmcisteri Shuckard) 



4. Antennae Q-jointed 5 



Antennae io-12-jointed 7 



5. Head in large individuals with the margins parallel or wider be 



fore than behind; clypeus in small specimens not prominent 6 



Head narrowed anteriorly; clypeus prominent. .. .Alaopone Emery 



(Type, Typhlopone cartcri Shuckard) 



6. Head a little longer than wide ; abdominal petiole in large and 



medium sized individuals with a thorn beneath towards apex ; 



pygidium tridentate Alaopone Emery 



Head in large individuals much longer than wide ; abdominal peti 

 ole with only a prominent angle -beneath ; pygidium simple, 



Rhogmus Shuckard 

 (Type, R. nmbriatus Shuckard) 



7. Mandibles at apex with a short, bidentate cutting margin; antennae 



n-jointed 8 



Mandibles in large individuals without a cutting margin, sabre- 

 shaped ; in smaller forms with a tooth at the apical third ; an 

 tennae in large and medium sized forms 12-jointed, in small and 



the smallest forms 10 or n-jointed Dichthadia Gerstacker 



(Type, D. furcata Gerstacker) 



8. Abdominal petiole always distinctly longer than wide, 



Typhlopone Westwood 

 (Type, T. fulva Westwood) 



a Zool. Jahrb. Syst, vm, 1895. 



