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sexual insects, which may take place either before or after the division 
of the colony. 
DETERMINATE AND INDETERMINATE COLONIES. 
An insect colony in which all the eggs are furnished by a single 
laying queen is a strictly determinate organization; that is, it reaches 
a natural limit after the mother insect dies or ceases to produce. The 
queens of ants and termites are sometimes enormously fertile and live 
for many years, so that determinate colonies may sometimes attain 
large size. 
Colonies may be called indeterminate when the social economy of 
the insect is such that a lost queen can be replaced. This is the case 
with the honeybee, which may be said to have a simple indeterminate 
colony because each hive has but a single laying queen. Colonies 
with more than one ege-producing queen may be called compound 
indeterminate. This condition has been reached in two different 
ways. Some of the termites, for example, are able to replace a lost 
queen by what are called complemental queens, individuals which are 
brought to a precocious sexual maturity, but without becoming fully 
winged. Other termites, such as the South European Zermes Tuci- 
fugus studied by Grassi, seem to have gone over entirely to the com- 
plemental queen basis, thus reaching a completely indeterminate 
organization. With the ants the same result has been reached in a 
slightly different manner. Some of the young queens are fertilized 
and drop their wings before emerging from the parental nest, and, 
being tolerated by their mother and sisters, they remain to contribute 
to the numerical prosperity of the family. 
A condition very similar, superficially, to that of the clustered col- 
onies of the keleps is to be found in certain ants and termites which 
have the habit of making what might be called multiple nests. In- 
stead of constructing a single compact dwelling, a colony may spread 
out into several distinct burrows or nests, connected by galleries, 
sometimes very long. - An instance of this among the ants has been 
cited already on page 27. In one species of the termites, a single col- 
ony often builds numerous nests of considerable size on widely sepa- 
rated branches of the same or neighboring trees in the forests of 
Liberia. The queen, however, does not live in these aerial summer- 
houses, the eggs being carried up by the nurses through the galleries 
which connect with subterranean burrows. 
It is conceivable, however, that the compound indeterminate colony 
might have originated in a more direct manner among insects which 
have never passed through the determinate stage of social organiza- 
tion. Social organization probably began, as already suggested, with 
