294 MODERN CLASSIFICATION OF INSECTS. 
Gould (p. 35.), those which are destined for the necessary supply of 
future females, males, and neuters, are deposited at three different 
pericds. We are ignorant, however, of the peculiar circumstances by 
which the abortiveness of the neuters is effected. In the hive bee. 
this is known to be produced by the female larve being fed with a 
less nourishing kind of diet than that which is given to the larve 
which are to produce fruitful females or queens; but the differences 
which exist between the female and neuter ant are far more striking 
than those between the queen and worker bees. In the ants, for 
instance, not only are the organs of sex obliterated in the workers, but 
they have a thorax of a totally different form from that of the females, 
and are moreover destitute of wings; the period when this loss of the 
wings and modification in the form of the thorax takes place, is pro- 
bably simultaneous with that when the sexual organs are rendered 
abortive; but the circumstances connected therewith, although of 
great physiological interest, have not been yet observed. Another 
peculiarity also exists ; namely, that certain individuals, few in number, 
amongst the neuters, are of a larger size, and furnished with much 
larger heads than the ordinary workers.* These individuals were 
first observed by Gould, and subsequently by Latreille; and they 
appeared to the former to be equally employed in the labours of 
the nest with the ordinary workers, although Huber could not as- 
certain their office in the nests of F. rufescens. According to M. De 
la Cordaire, these specimens (at least in a South American species 
allied to Atta cephalotes) appeared to be employed as defenders of 
the nests, and in capturing in their excursions. I have already also 
alluded to the existence of two kinds of workers belonging to the 
Eciton hamata; and Latreille has noticed other species in which 
he has found this “ variété constante,” especially in F. structor, the 
difference in size between the two kinds of neuters of the latter being 
so great that they would be mistaken for different species. We are, 
however, indebted to M. Lund for a more precise notice of the em- 
ployment of these few large-headed neuters in a Brazilian species of 
Myrmica. Having observed a column of ordinary neuters issuing 
from an aperture in the ground, each loaded with food, he perceived 
that the aperture was guarded by four of these large-headed_ indi- 
viduals, a few ef which were also noticed in the column, but not 
* A similar cireumstance also occurs amongst the neuters of the hive bees. Huber 
has named the smaller individuals “ abeilles nourrices,” and the larger ones, which 
secrete wax, ‘abeilles ciriéres.” 
