100 GENERA OF HYMENOFfERA. 



11.— Thorax strongly constricted between nieao- and metathomx ; niandible.s very 

 broad; frontal area small, clearly defiiied ; antennte 12 jointed (the 

 mi^or worker has the head enormously developed, short, more than 

 twice as broad as the thorax, the frontal groove very deep, travei-sing 

 the vertex and dividing the buck of the head into two convex lobes). 



Fheidole Westw. 

 Thorax slightly or not at all strangulated between ♦ .c meso- and meta- 

 thorax. 



Lateral bii-sal margin of clypeus distorted or i-levatcd between frontal 

 carinte and insertion of mandibles, forming a ])rojecting ridge; thorax 

 short, erect, slightly impressed between meso- and metjithorax, ])rotho- 

 rax with the shoulders angular, metatliorax with two spines; tibial 

 spurs simple; antennas 12-jointed ; maxillary i>alpi (i-jointed, labial 

 palpi 3-jointed Tetramoriuni Mayr. 



Lateral basal margin of clypeus not elevated ; thorax elongate, mori- than 

 twice as long as high, little or not impressed between meso- and meta- 

 thorax, prothorax with shoulders rounded, metathomx with two spines; 

 no tibial spurs: antennsB 11 -12-joiuted ; frontal area not clearly defined ; 

 maxillary palpi 5-jointed, labial palpi 3-joiuted.Ijeptotliora.v Mayr. 



Females. 

 Anieunal foveje terminated outwardly by a carina; clypeus interposed between 

 insertion of antennte ; frontal carina? placed in middle of anterior part 

 of the head ; antennre 11-jointed ; head triangular, with a small tooth 

 on each side behind ; thorax viewed from above large, ovate; metatlio- 

 rax with two small teeth ; abdomen subglobosc. .second joint of petiole 

 short and broad ; wings with one submargiual cell, which like the mar- 

 ginal is long and narrow, nt) discoidal cell Atta Fabr. 



Antennal fovese without external carina 2 



2.— Clypeus not interposed between insertion of antennae 3. 



Clypeus interposed between insertion of antennae ; frontal carinse placed in 



middle of anterior part of the head 4. 



-i. — Frontal carime placed in middle of anterior part of the head ; eyes large, 

 elongate-ovate, occupy"' '^ a large portion of lateral margin of the head ; 

 antennse inserted close together near anterior margin ; first joint of 

 petiole pedunculate, nodose at tip, second joint globose ; antennse 12 



(or 13?) jointed RNeudomyrma Guer. 



Frontal carinse placed on lateral margin of the head, defining large, elon- 

 gate antennal fovea', the concavity of which is not visible from above ; 



antennse fi-jointed StruniigeiiyN Smith. 



4.— Petiole attached to upiier basal surface of abdomen, which is cordiform, de- 

 pressed above, convex beneath, acuminate at tip; metatliorax i-arely 

 unarmed; antennre 11-jointed: wings with one complete submarginal 



and one discoidal cell C'remastogaster Lund. 



Petiole attached to the ba.sjil middle of abdomen, which is oval 5. 



n. — First joint of jietiole nearly cubical ; clypeus short, with two longitudinal 

 crests which are terminated in front by two obtuse teeth ; antennaj 12- 

 joiuted; metathorax with two spines posteriorly; wings dark colored, 

 hairy, margins ciliated, one complete submarginal cell, no discoidal. 

 marginal cell short, closed, appendiculate Myrinecina Curtis. 



