HYMENOPTERA. 117 
FAMILY I. 
HETEROGYNA. 
The first family of our second section is composed of two or 
three kinds of individuals, the most common of which, the neu- 
ters and females, are apterous, and but rarely furnished with 
very distinct ocelli. | 
Their antenne are always geniculate, and the ligula is 
small, rounded and concave, or cochleariform. 
Some form communities in which we find three kinds of 
individuals, of which the males and females are winged, and 
the neuters apterous. In the two last the antenne gradually 
enlarge, and the length of.their first joint is at least equal to 
that of the third of the whole organ; the second is almost as 
long as the third, and has the form of a reversed cone. The 
labrum of the neuters is large, corneous, and falls perpendi- 
cularly under the mandibles. 
These Hymenoptera compose the genus 
Formica, Lin.(1) 
Or that of the Ants, so highly celebrated for their foresight, and so 
well known, some by their depredations in our houses, where they 
attack our sugar and preserved viands, communicating to them at 
the same time a musky and disagreeable odour, and others by the 
injury they do to our trees, by gnawing their interior in order to 
form domicils for their colonies. 
The abdominal pedicle of these Insects isin the form of a scale 
or knot, either double or single, a character by which they are 
easily recognized. - Their antenne are geniculate, and usually 
somewhat largest near the extremity; the head is triangular, with 
oval or rounded and entire eyes, and the clypeus large; the mandi- 
bles are very strong in the greater number, but vary greatly as to 
(1) The tribe of the Formicarr#, Lat., Fam. Nat. du Régn. Anim., 452. 
