1NSECTA. 



of Fabricius, differs from the ants by their very minute palpi, and by the large 

 size of the heads of the neuters. In this genus is 

 included some of the largest species of ants, some 

 of them exceeding an inch in the length of the 

 body. The Formica cepha'otes of Linnaeus and 

 Fabricius is the type of this genus : it inhabits 

 various parts of South America, where from its 

 habits it has received the name of the visiting- 

 ant, " la fourmi de visite," since it occasionally 

 Magnified Atta Cephaiotes. finds its way in troops into the houses of the resi- 

 dents, who open their doors and receive it gladly, as it consumes or drives 

 away not only the cockroaches and spiders, but even mice and rats. 



The remaining Heterogyna are solitary insects. Each species is composed 

 of but two kinds of individuals, winged males and apterous females ; the latter 

 are always armed with a powerful sting. The antennae are filiform or seta- 

 ceous, and vibratile; their first and third joints are elongated, and the length 

 of the first is never equal to the third of the total length of the whole organ. 

 They form the genus 



MUTILLA, Linnaeus. 



These insects are found in hot and sandy localities. The female runs with 

 great quickness, and is always seen on the ground. The males frequently 

 alight on flowers, but their mode of life is unknown. 



FAMILY II. 

 FOSSORES*. 



THE second family of this section comprises those Hymenoptera armed with 

 a sting, in which all the individuals of both sexes are furnished with wings, 

 and live solitarily ; and in which the legs are exclusively adapted for walking, 

 and in several for digging. The ligula is always more or less widened at its 

 extremity, and never filiform or setaceous. The wings are always extended. 



They compose the genus 



SPHEX, Linn feus. 



Most females of this genus place beside their eggs, in the nests they have 

 constructed, most commonly in the earth or in wood, various insects or their 

 larvae, and sometimes Arachnides, previously pierced with their sting, to serve 

 as food for their young. The larvae are always destitute of feet, resemble 

 little worms, and undergo a metamorphosis in the cocoon they have spun pre- 



* Diggers. 



