Wasps, Bees, and Ants 



535 



the sting is rudimentary, short and blunted, and no longer a weapon. The 

 mandibles are relied on by the stingless ants as means of defence and offence. 

 An ant species always includes at least three kinds of individuals, as a 

 social wasp or bee species does, and may include several more (Fig. 738). 

 There are always winged males, 

 which die soon after their issu- 

 ance from the nest to take part 

 in the mating-flight swarm, and 

 winged females, or queens, which 

 pull off their wings immediately 

 after this flight. Thus winged 

 ants are to be seen only at cer- 

 tain seasons of the year, the 

 fertile females when found in 

 the nest being almost always in FlG . 73 8. A California black ant, species un- 

 wingless condition. In addition determined, showing winged forms and wing- 

 i . j. ., less worker. (After Jordan and Kellogg; 



to the winged individuals there twice natural size \ } 



are wingless workers which are 



infertile females, i.e., with rudimentary egg-glands and lacking also the 

 spermatheca. These workers in many species, probably most, are of two 

 sizes, worker minors and worker majors; the two are not wholly distinct, 



a 



FIG. 739. FIG. 740. 



FIG. 739. Soldier (a) and worker (c) of Pheidole lamia; b, head of soldier in profile. 



(After Wheeler; much enlarged.) 

 FIG. 740. Male (a) and ergatoid female (>) of Tomognathus subl&vis. (After Wheeler; 



much enlarged.) 



however, as intermediate sizes are occasionally to be noted. In addition 

 there may exist workers with extra-large heads and jaws which are known 

 as soldiers (Fig. 739), but also between these and ordinary workers interme- 



