46 HYMENOPTERA. 



nent on the vertex. Thorax elongate, narrow and compressed 

 behind ; the divisions of the thorax not very strongly marked ; 

 legs elongate and slender ; the tibiae with a few fine scattered 

 spines or hairs. Abdomen ovate, with a few pale hairs at the 

 apex ; the scale of the petiole incrassate, and, viewed sideways, 

 wedge-shaped. 



Female. Length 5 lines. Very closely resembles the worker, 

 differing only in the form of the thorax, which is of a more ovate 

 form, as in the majority of species, and in having wings, the 

 neuration of which is the same as in F. ligniperda ; the antennae 

 are elongate and slender, as in the worker. 



Hab. Brazil (Ega). 



This is a very remarkable insect; for, independent of the 

 enormously developed eyes and produced clypeus, the palpi are 

 elongated to half the length of the thorax, the maxillary are six-, 

 and the labial four-jointed. Mr. Bates says, " This curious solitary 

 ant is never seen by more than one at a time, prowling about 

 fallen leaves, &c. in the forest ; I have never seen its Formicarium, 

 and, from its solitary habits, have no clue to guide me in looking 

 for it." 



152. FORMICA MELANOCEPHALA. 



Formica melanocephala, Fabr. Ent. Syst. ii. 353. 13. 



Coq. Illustr. dec. 1. t. 6. f. 8. 



Latr, Hist. Nat. Fourm. 269. 

 Lasius melanocephalus, Fabr. Syst. Piez. 417. 5. 



Hab. Cayenne. 



153. FORMICA PALLIPES. 



Formica pallipes, Fabr. Ent. Syst. ii. 356. 28. 

 Latr. Hist. Nat. Fourm. 284. 



Hab. Cayenne. 



154. FORMICA SERICEIVENTRIS. B.M. 



Formica sericeiventris, Guer. Voy. de la Coq. Zool. ii. 205 $ 

 Formica cuneata, Perty, Del. An. Art. p. 134. t. 27. 1 . 



Hab. Rio Janeiro (Constancia) ; Columbia; Brazil; Mexico. 



The descriptions of Guerin and Perty are of the large form of 

 the worker; the female is from 8 to 10 lines long, and differs 

 from the worker major in having the thorax oblong-ovate and 

 broader in proportion to the head ; in having ocelli which are 

 small and placed rather forward, the anterior ocellus being in a 



