50 HYMENOPTERA. 



The insect which we suppose to be the female of this species, 

 is from Santarem ; it very closely resembles the F. ligniperda ; 

 the flagellum, legs, thorax beneath, pale ferruginous ; in some 

 specimens the metathorax is also pale, others have also the pro- 

 thorax pale, and two pale longitudinal stripes on the disk of the 

 thorax ; the base of the abdomen is usually pale, as well as the 

 basal segments beneath ; the wings hyaline, with a yellow tinge 

 at the anterior margin of the superior pair, the nervures pale fer- 

 ruginous. 



l/l. FORMICA BIMACULATA. 



Worker. Length 2J lines. Black and shining, with a trans- 

 verse oblong white macula on each side of the second segment 

 of the abdomen at its base, sometimes the maculae form a slightly 

 interrupted fascia ; some of the large workers have the head red. 

 Head oblong, with the mandibles and antennae rufo-piceous ; 

 eyes rather large, prominent, and nearly circular. Thorax ob- 

 long, narrower than the head, compressed behind; the knees 

 and the tarsi rufo-piceous. Abdomen ovate, with a few scattered 

 glittering pale hairs ; the scale of the peduncle incrassate, narrow, 

 its margin above rounded ; the legs a.nd antennae pubescent. 



The large worker only differs in being half a line larger, and 

 in having the head red. 



Hat. St. Vincent's. (Coll. F. Smith.) 



1/2. FORMICA ALBIPENNIS, 



Formica albipennis, Fabr. Ent. Syst. ii. 354. 19. 



Latr. Hist. Nat. Fourm. 278. 

 Lasius albipennis, Fabr. Syst. Piez. 41 / 



Hab. Island of St. Cruz. 



173. FORMICA OVATICEPS. 



Formica ovaticeps, Spin. Faun. Chili, vi. 238. 3. 



Hab. Chili. 



174. FORMICA MOROSA. B.M. 



Worker. Length 3 lines. Opake black : the flagellum ferru- 

 ginous with the apex black. Head elongate, eyes ovate, placed 

 rather high on the sides of the head ; the mandibles ferruginous, 

 the clypeus with a central longitudinal carina, the head rounded 

 behind. Thorax not quite so wide as the head, much com- 



