10 
pastured, and cleaned with as much care as modern dairy catile. 
Some ants have also a highly developed slave-making instinct, and 
undertake regular raids on the nests of other species to capture their 
young and carry them away to be brought up in servitude. 
Tt would seem, therefore, that in the highest members of both 
groups of social insects the chief purpose served by this simultaneous 
emergence, or “ swarming,” as it is commonly called, is interbreeding, 
or cross-fertilization, rather than the founding of new colonies in 
more distant localities, as hitherto supposed. This may explain why 
the species of these insects have achieved nothing very remarkable in 
the way of geographical distribution, in spite of the immense fecun- 
dity of their females. A single individual ant or a pair of termites 
might be able to establish a colony in a new locality, but the lack of 
opportunities for cross-fertilization might prevent the perpetuation 
and further extension of the specées, which could increase its range 
only by gradual, continuous expansion. 
BREEDING HABITS OF THE KELEP. 
With such instances in mind it becomes easier to appreciate the fact 
that the breeding habits of the kelep differ notably from those of the 
termites and termite-like ants, and approach those of the domestic 
honeybee. Although the actual migration has not been observed, 
there are strong indications that, instead of emitting annual broods of 
sexual individuals and founding colonies by means of solitary fecun- 
dated females, the kelep communities simply subdivide after the 
fashion of the bees, or in a still more practical and business-like man- 
ner, the problem of cross-fertilization having been solved in another 
aThe extreme development of the pastoral instinct is to be found in an ant 
which takes care of the eggs of its plant-lice cattle through the winter. 
“It is not merely that the ants mill them, defend them from attack, some- 
times protect them by earthen inclosures from too great summer heat, but over 
and above all this they collect the eggs in autumn, keep them through the 
winter, and plant them out on their proper plant in the spring. Some of the 
root aphides may always be found in ants’ nests, but I was much puzzled 
years ago by finding in ants’ nests some black eggs which obviously were not 
those of ants. Eventually I ascertained that they belonged to a species of 
aphis, which lives on the leaves and leaf stalks of plants. 
“These eggs are laid early in October on the food plant of the insect. They 
are of no direct use to the ants, yet they are-not left where they are laid, ex- 
posed to the severity of the weather and to innumerable dangers, but are brought 
into their nests by the ants and tended by them with the utmost care through the 
long winter months until the following March, when the young ones are brought 
out and again placed on the young shoots of the daisy. This seems to be a most 
remarkable case of prudence. Our ants may not, perhaps, lay up food for the 
winter, but they do more, for they keep during six months the eggs which will 
enable them to procure food during the following summer, a case of prudence 
unexampled in the animal kingdom,’—Avebury, 1905, The Open Court, 19: 190. 
