INSECTA. 365 
Sp. Atta cephalotes FaBr., Pormioa cephalotes L.., Dk GrEr, Ins. 111. Pl. 31, 
fig. 11, Latr. Fourmis, Pl. 1x. fig. 57, Kotuar, Brasil. voziigl. last. Ins. 
fig. 10. The neuters are five lines long with a very large head, heart- 
shaped, armed behind with two small spinules, chestnut-brown all over. 
These ants can strip whole trees of their leaves in a few hours. In Suri- 
nam and Brazil}. 
Add sub-genera: Cryptocerus Latr., Stenramma Westw., Myrme- 
emma Curtis, Myrmecaria Saunpers, Carebara Westw., Solenopsis 
Westw., Pheidole WEstw. 
Comp. J. O. WEstwoop, Descriptions of several exotic species of Ants, 
Ann. of nat. Hist. VI. pp. 86—89. 
Sub-genera Myrmica Later. (and Heriton ejusd.). Maxillary palps 
long, with six joints. 
Sp. Myrmica rubra, Formica rubra L., Fasr., SWAMMERDAM, Bijbel d. nat. 
Tab. xvi. figs. 1—13. Larreinin, Fowrmis, Pl. x. f. 62. Comp. on this 
ant, whose sting he has also figured, LEEUWENHOECK, 58e, Missive von 9 Sept. 
1687, Vervoly der Brieven, bl. 97—107. 
B. Petiole of abdomen with a single joint. 
Ponera LAtTR. Females and neuters aculeate. 
Add sub-genera: Odontomachus Latr. (Daceton Perty does not 
differ from Odontomachus, on WrEstwoop’s authority), Condylodon 
Lunp, T'yphlopone Westw., Anomma SHUCK. 
Comp. SHucKARD, Ann. of Nat. Hist. v. pp. 326—328; Wusrwoon, 
ibid. VI. pp. 81—85. 
Formica Latr. (spec. from gen. Formica L.) Sting none. 
Add sub-genus: Polyergus Latr. 
Sp. Formica rufa L., Larr., Fourmis, Pl. v. fig. 28, AB, (fem. Formica 
dorsata PANZER, Deutschl. Ins. Heft 54, Tab. 1). This species, without a 
sting, affords the formic acid (Acidum formicarum s. formicicum, acide for- 
mvique), a secretion from glands in the abdomen of the females and neuters. 
This acid is constantly fiuid, colourless, of a pungent smell and sharp 
taste. Fourcroy and VAUQUELIN were of opinion that it consists of a 
mixture of acetic and malic acid; but the experiments of GEHLEN and 
others have shewn that it is a peculiar acid. 
Formica rufescens LAtTR., Fourmis, p. 186, Pl. vit. fig. 38; this species 
robs the nests of other species of ants of the larvee and pupe of neuters, 
and carries them to its nest, where they are brought up with the young of 
their robber by neuters which have proceeded from larvze and pupe stolen 
1 Ants are very numerous in South-America, and, by removing dead animals and 
destroying other insects, perform the same office in the economy of nature with the 
Carabici and Dermestes and other Clavicornes. The natives also eat ants. Smoked 
ants (Vachacos) are a favourite article of food with the Indians at the Rio-negro ; 
V. Humsowpr’s Reise in dic Aquinoctial-Gegenden, iv. 8. 318. 
