INSECTA. 365 



Sp. Atta cephalotes FABR., Formica cephalotes L., DE GEER, Ins. m. PI. 31, 

 fig. ir, LATR. Fourmis, PI. ix. fig. 57, KOLLAR, 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 1 . 



Add sub-genera : Cryptocerus LATE., Stenamma, WESTW., Myrme- 

 cina CURTIS, Myrmecaria SAUNDERS, Carebara WESTW., Solenopsis 

 WESTW., Pheidole WESTW. 



Comp. J. 0. WESTWOOD, Descriptions of several exotic species of Ants, 

 Ann. ofnat. Hist. vi. pp. 86 89. 



Sub-genera Myrmica LATR. (and Ecriton ejusd.). Maxillary palps 

 long, with six joints. 



Sp. Myrmica rubra, Formica rubra L., FABR., SWAMMERDAM, Bijbel d. not. 

 Tab. xvi. figs, i 13. LATREILLE, Fourmis, PI. x. f. 62. Comp. on this 

 ant, whose sting he has also figured, LEEUWENHOECK, 586, Missive von g Sept. 

 1687, Vervolgder Brieven, bl. 97 107. 



B. Petiole of abdomen with a single joint. 

 Ponera LATR. Females and neuters aculeate. 



Add sub-genera : Odontomachus LATR, (Daceton PERTY does not 



differ from Odontomachus, on WESTWOOD'S authority), Condylodon 



LUND, Typhlopone WESTW., Anomma SHUCK. 



Comp. SHUCKARD, Ann. of Nat. Hist. v. pp. 326 328 ; WESTWOOD, 

 ibid. vi. pp. 8 1 85. 



Formica LATR. (spec, from gen. Formica L.) Sting none. 

 Add sub-genus : Polyergus LATR. 



Sp. Formica rufa L., LATR., Fourmis, PI. v. fig. 28, AB, (fern. Formica 

 dorsata PANZER, Deutschl. Ins. Heft 54, Tab. i). This species, without a 

 sting, affords the formic acid (Acidum formicarum s. formicicum, acide for- 

 mique), a secretion from glands in the abdomen of the females and neuters. 

 This acid is constantly fluid, 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 LATR., Fourmis, p. 186, PI. vn. fig. 38; this species 

 robs the nests of other species of ants of the larvae and pupae 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 larvse and pupce 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 ( Vacliacos) are a favourite article of food with the Indians at the Rio-negro; 

 V. HUMBOLDT'S Reise in die ^Equinoctial- Geycnden, iv. s. 315. 



