592 INSECTA. 



sexes takes place in the air, where the winged individuals form large swarms, after which the males 

 soon die, without again entering their former ahode. The females, now ready to become mothers, quit 

 the neighbourhood, and, having first pulled ofi' their wings with their feet, become the foundresses of 

 new and distant colonies. Some are, however, made prisoners by the neuters of the parent colony, 

 who strip them of their wings, in order that they may deposit their eggs, after which it is believed 

 that they are driven olf. 



The neuters, distinct not only by their want of wings and ocelli, but also by the size of the head, 

 the strength of the jaws, the thorax more compressed and often nodose, and the legs proportionably 

 longer, are alone charged with the works of the nest and rearing of the young, the nature and form of 

 the former of which varies according to the instinct of the different species. They are more generally 

 established in the ground, some using only particles of earth, and having their nests entirely hidden, 

 and others covering their nests with bits of stick, straws, &c., forming a conical mound. Some inhabit 

 the trunks of old trees, which they pierce in every direction. The neuters feed the young grubs, and 

 move them on fine days to the outer surface of the nest, in order to give them heat, and removing 

 them back again at the approach of night or bad weather ; they defend them from their enemies, and 

 take the greatest care of them and of the pupse, especially when the nests are disturbed. Some of the 

 latter are inclosed in a cocoon, whilst others are naked : the neuters also tear open the cocoon when 

 the period of the final change arrives. 



Different nests have exhibited to me neuter individuals (few in number) remarkable for having a 

 much larger head than the ordinary neuters ; M. Lacordaire also gave me a neuter Ant allied to Atta 

 cephalotes, Fal)., assuring me that the individuals of this kind are the defenders of the society, and 

 appear to perform the duty of captains in their excursions. 



The name of Ant-eggs is commonly given to the larvae and pupae. Those of T. flava are used for 

 feeding young Pheasants. The neuters prevent the perfect insects, which have recently acquired their 

 wings, from leaving the nest until a favourable opportunity, dependent upon the heat of the 

 atmosphere. 



The majority of Ants' nests are entirely composed of a single species, but Nature has departed from 

 this plan in F. {Polyergns) rufescens, or the Amazon Ant, and F. sanguinea. The neuters of these two 

 species seize by violence auxiliaries or slaves of their own caste (neuters), but of different species, 

 namely, F. cunicularia, Latr., and F. fusca, Linn. When the heat of the day begins to dechne, and 

 regularly at the same hour, at least during several days, the Amazon Ants quit their own nests in a 

 close and numerous column, and direct their course to the ant-hill they intend to attack, and which 

 they enter, in spite of the opposition of the owners, and carry off in their jaws the larvae and pupae of 

 the neuters of these Ants, and which they take to their own nest, where they are tended by other 

 neuter slave Ants of the same species, which have been previously stolen in a similar manner, and 

 which also take charge of the young of these amazon conquerors. Such is the composition of a 

 mixed Ant-nest. 



It is known that Ants are very fond of the saccharine liquid which exudes from the bodies of Aphides 

 and CoccidcB; four or five species also collect the Aphides, and even their eggs, which they keep at 

 the bottom of their nests, especially in bad seasons. Others construct galleries of earth from their 

 nests along the stems of branches of trees, as far as the twigs peopled by the Plant-lice. 



The winged Ants perish at the commencement of the cold weather, but the neuters pass the winter 

 dormant in their nests ; their prudence, so much celebrated, has no other end than to augment and 

 consohdate their habitation with all kinds of matters ; for a store of food would be useless in a season 

 when the insects could not use it. 



The habits of exotic, and especially tropical Ants, are almost unknown. The Visiting Ant performs 

 some service to our colonists by driving away Rats, and a quantity of other obnoxious insects ; but 

 other species are obnoxious from the destruction which they make, and which it is impossible to prevent. 

 I divide the genus Formica in the following manner : — 



1. Formica proper, destitute of a sting ; the antennae inserted near the forehead ; mandibles triangular and den- 

 ticulated ; the abdominal peduncle consists of a single knot. Formica rtt/a, Linn, [the great Horse Ant, or Pis- 

 mire], common in woods, where it forms nests like a large sugar loaf or dome, composed of earth, fragments of 

 wood, &c., and which are often of large size ; the winged individuals appear in spring. F. fusca, cunicularia, and 

 a great number of species. 



