of some Species oj Brazilian Ants. 161 



at the base; the second joint a little shorter than the first, truncate 

 at the apex : the labial palpi 3-jointed ; tlie basal joint longest, 

 the apical one shortest, its apex truncate. Workers, of two 

 sizes ; the larger individuals, in some species, having their mandi- 

 bles protruded in an elongate curve, sickle-shaped, acute at their 

 apex ; the smaller workers having the mandibles short, curved, 

 broad and flattened in the middle; their apex acute: the tongue 

 and palpi, when in repose, covered and protected by the labrimn, 

 which is convex, large and transverse, its inferior margin rounded ; 

 head large, wider than the thorax, in some individuals dispropor- 

 tionately large ; eyes very minute, placed somewhat backwards 

 and within the sides of the head, not visibly reticulated : the ocelli 

 obsolete in the workers. Thorax unarmed ; abdomen with two 

 nodes at its base. The males and females not known. 



Sp. 1. Eciton hamata. 



Formica hamata, Fabr. Ent. Syst., ii. 364, 58 ; Latr. Hist. Nat. 



Fourm., p. 242, tab. 8, fig. 54. 

 Mijrmica hamata, Fabr. Syst. Piez., p. 425, G. 

 Eciton hamata, Latr. Gen. Crust, et Ins., iv, 129. 

 Ancijlognathus, Lund. Ann. Soc. Nat., xxvii, 

 Camptognatha, Westvv. GrifF. Anim. King., xv. 51C, tab. 70, 



fig. 4. 



Worker. — Length 4 — i| lines. Antennae longer than the head 

 and thorax ; the flagellum sub-filiform and pubescent, the pube- 

 scence short and scattered ; the head very large, full twice the 

 width of the thorax, widest in front, and armed behind with two 

 short spines of a pale yellow-testaceous colour ; smooth, shining 

 and thinly sprinkled with short pale hairs ; mandibles elongate, 

 sickle-shaped, and bent suddenly inwards at their apex, forming 

 a pointed hook ; sometimes rufo-piceous, sometimes black. The 

 thorax, legs and abdomen of an opaque reddish yellow, the tarsi 

 fuscous : the nodes of the abdomen without spines beneath ; the 

 abdomen ovate ; the entire insect thinly sprinkled with pale pu- 

 bescence. 



This insect is exceedingly abundant in Brazil; Mr. Bates has 

 observed its legions in processions of great extent, but up to the 

 present time has been unable to meet with the other sexes ; this, 

 however, he hopes to accomplish, but the societies are so numerous 

 and the sting of the insects so severe, that an attack on one of 

 their colonies for that purpose is not to be rashly undertaken. 



VOL. HI, N.S. PART V. — JULY, 1855. M 



