WARRIOR ANTS, AND THEIR EQUIPMENT 



and jaws, the important parts in attack and defence. 

 But in other species the process has advanced to a 

 distinct soldier caste whose characteristics are most 

 decided. 



In the genus Pheidole we have species in which the 

 functions of workers and soldiers are clearly separate. 

 Of a Texas species, Pheidole instabilis, the workers alone, 

 though of comparatively diminutive size, manage the 

 colony's affairs. Thev forage for seeds or dead insects, 



^ */ 



which they drag to the nest. They dig out the galleries, 

 carry about and tend the larvae and pupae, even the huge 

 female ones, and assist to cut out the callows from their 

 pupal envelopes. On the other hand, the soldiers have 

 an office for which their abnormally large heads and 

 strong jaws peculiarly fit them: they are the guardians 

 of the nest. They form a sentinel cordon around the 

 young brood and the callow antlings. They are stolid 

 and inactive, keepers at home, but eschew the task of 

 tending the communal babies. Their heads are so large 

 proportionately to their bodies, that if turned upon 

 their backs they are often unable to right themselves, 

 and if not relieved may die practically standing on their 

 heads. 



This big-headedness, with its corresponding develop- 

 ment of the jaws, however, has led to a peculiar service. 

 The soldiers act as the communal carvers or trenchers, 

 and crack the shells of the oily seeds and the tough, 

 chitinous cases of the insects which the foragers collect 

 for the commissary department (see chap. iv). Some- 

 what oddly, they abstain from levying toll upon the 

 food supplies thus made ready for general use, but draw 

 their rations directly from the comminuted stock in the 

 workers' crops. [W. 6, p. 4.] 



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