JOINTED-LIMBED ANIMALS AS MESSMATES 177 
and hunting about, as if aware of the propinquity of the object 
of their search, yet ignorant of its exact position. At last they 
discover the settlement, and the foremost of the invaders, rushing 
impetuously to the attack, are met, grappled with, and frequently 
killed by the negroes on guard; the alarm is quickly communi- 
cated to the interior of the nest; the negroes sally forth by 
thousands, and, the red ants rushing to the rescue, a desperate 
conflict ensues, which, however, always terminates in the defeat 
of the negroes, who retire to the innermost recesses of their habi- 
tation. Now follows the scene of pillage; the red ants with their 
powerful mandibles tear open the sides of the negro ant-hill, and 
rush into the heart of the citadel. In a few minutes each of the 
invaders emerges, carrying in its mouth the pupa of a worker 
negro, which it has obtained in spite of the vigilance and valour 
of its natural guardians. The red ants return in perfect order 
to their nest, bearing with them their living burdens. On reach- 
ing the nest the pupze appear to be treated precisely as their own, 
and the workers, when they emerge, perform the various duties 
of the community with the greatest energy and apparent good- 
will; they repair the nest, excavate passages, collect food, feed 
the larve, take the pupz into the sunshine, and perform every 
office which the welfare of the colony seems to require; in fact, 
they conduct themselves entirely as if fulfilling their original 
destination.” The Amazon Ants are practically incapable of 
feeding themselves, being thus almost entirely dependent upon 
the good offices of their slaves. They are, however, so fierce and 
warlike that their dominance in the mixed community is easily 
understood. Far more remarkable is the mode of life of a rare ant 
(Anergates atratulus), native to Central Europe, in which there 
is no worker caste, but only females and wingless males, both 
sexes being weak and helpless. Small numbers of them are 
found associated with numerous workers of a small species 
(Zetramorium cespitum), by which they and their offspring 
are tended, and which are vastly their superiors in strength and 
energy. How the association comes about is unknown, but it 
has been suggested that a young fertile Anergates female makes 
her way into a Tetramorium nest, destroys the queen and young, 
and is accepted by the workers as their nominal sovereign. A 
more likely view is that such a female enters a Tetramorium nest 
containing only workers, and it appears that such nests do some- 
Vou. IY. 406 
