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_— 
INTERRELATIONS OF INSECTS 3 
species may occur. In some species of ants several types of 
workers exist; these are distinguished by structural peculiari- 
ties of one kind or another, which possibly indicate special 
functions, for the most part as yet unascertained. Further- 
more, the sexual individuals are not necessarily winged; some 
or all of them may be wingless, especially the females. These 
wingless males and females are termed ergatoid, on account 
of their resemblance to workers. 
As to how these various forms are produced, very little is 
known. Probably, as among bees, workers and queens are 
produced from the same kind of eggs, which have been ferti- 
lized, and the differences between worker and queen and _ be- 
tween workers themselves may be due to the quality and quan- 
tity of the food that is supplied to the larvee by their nurses. 
As in bees, the parthenogenetic eggs laid by abnormal workers 
may produce males, as Forel, Lubbock and Miss Fielde have 
found; or they may produce normal workers, as Reichenbach 
and Mrs. A. B. Comstock have found to be the case in Lasius 
niger. Wheeler points out the possibility of the inheritance 
of worker characters through the male offspring of workers. 
Larve.—The numerous eggs laid by one or more queens 
are taken in charge by the young workers, through whose 
assiduous care the helpless larvee are carried to maturity. The 
nurses feed the larve from their own mouths, clean the larve, 
and carry them from one place to another in order to secure 
the optimum conditions of temperature, moisture, etc. When 
a nest is broken open, the workers seize the larve and pupz 
and hurry into some dark place. The pupa is either naked 
or else enclosed in a cocoon, spun by the larva. 
Nests.—The species of the tropical genus Eciton do not 
make nests but occupy temporarily any suitable retreat which 
they may happen to find in the course of their wanderings. 
Ants in general know how to utilize all sorts of existing cavi- 
ties as nests; they make use of crevices in rocks and under 
stones or bark, the holes made by bark-beetles, hollow stems 
or roots, plant-galls, fruits, etc. The extraordinary “ ant- 
plants ” have already received special consideration. 
