No. 22.] HYMENOPTERA OF CONNECTICUT. 577 



FORMICOIDEA. 



FORMICID^. 

 By William Morton Wheeler. 



The ants (family Formicid^) are social Hymenopterous in- 

 sects, and may be distinguished from the social bees and wasps 

 by having workers, or neuters, as they are less appropriately 

 called, without wings. They are, moreover, readily distinguished 

 from these and all other Hymenopterous insects by the following 

 characters : 



1. The first antennal joint in the workers and females, and 

 often also in the males, is greatly elongated and forms what is 

 known as the scape. The remaining shorter joints, constituting 

 the funiculus, or flagellum, are articulated at an angle with the 

 scape and can be folded up against it. 



2. One or two of the segments of the base of the abdomen 

 are much reduced in size to form a pedicel, and these segments 

 are either nodiform or bear an erect or inclined scale. When 

 only one of these segments is present, it is known as the petiole ; 

 when two are present, the first is the petiole, the second the post- 

 petiole. The swollen portion of the abdomen behind the pedicel 

 is known as the gaster, and has one more visible segment in the 

 male than in the female (queen). 



3. The legs of ants are distinguished from those of many 

 other Hymenoptera in having only one instead of two small 

 joints (trochanters) -between the hip (coxa) and femur. 



4. The venation of the wings of male and female ants is 

 much simplified and differs considerably from that of other 

 Hymenoptera. The female, or queen ant, unlike the queens of 

 the social bees and wasps, loses her wings after fertilization. 



The colonies of all our northern ants nest either in the ground 

 or in decaying wood. The nests, or formicaries, may be under 

 stones or logs, and always consist of irregularly excavated, inter- 

 communicating cavities, unlike the regular paper or waxen combs 

 of other social Hymenoptera. Often the nests are surmounted 

 37 



