212 Prof. 0. Heer on the House Ant of Madeira. 



found which not only cause much harm to cultivation, but also 

 force their way in enormous companies into the dwellings of 

 man, and thus become terrible pests of the country. One of 

 these kinds I had opportunity last year in Madeira to become 

 acquainted with. At first, by the ravages which it caused in my 

 dwelling, it occasioned me many annoyances; but afterwards, 

 when I began to pay attention to its habits, it afforded me much 

 amusement. I communicate these observations in the hope that 

 they will induce some of our young friends to institute similar 

 ones themselves, for which the richness of our environs in insects 

 affords such manifold opportunity. 



In the accompanying Plate (III.) is figured the small minute 

 Madeiran Ant. Fig. i. represents the female, fig. ii. the male ; 

 figs. III. & IV. the neuters, which present two very distinct forms. 

 The one (fig. iii.) has a remarkably large head ; it is larger than 

 all the rest of the body, and gives the little creature a most 

 extraordinary appearance ; in the other, the head is much smaller 

 and nearly circular. These small-headed ants are the working- 

 class of the colony, and form the mass of its population; we 

 shall therefore call them the labourers or workers. The large- 

 headed ants can scarcely amount to j-^oth of these, and serve 

 partly for the defence of the nest ; we shall therefore distinguish 

 them by the name of soldiers, from the rest. In still smaller 

 number appear the females, which not only are much larger than 

 the labourers, but are also distinguished by their transparent 

 glassy wings and shining brown colour. The males are not much 

 bigger than the labourers, and of a coal-black colour. Accord- 

 ingly, with these ants the family consists of four quite different- 

 looking individuals : of workers, soldiers, males, and females. 

 This ant-colony is consequently further developed than those of 

 our species, in which only one form of neuters (the common 

 wingless ants) occurs. 



The house-ant lives in very numerous societies, under stones 

 in the ground, and also under the bark of trees, and within the 

 walls of houses. The stones serve them, in common with all 

 ants living in the ground, in place of a roof for shelter. Their 

 nests go down pretty deep into the earth, and are divided into a 

 great number of passages and chambers. They have several 

 entrances, which are sometimes covered over, and run like 

 burrows under the stones. Not unfrequently they form their 

 nests in flower-pots standing before the windows and on the 

 balconies. 



They are found on the whole south side of the island of 

 Madeira, up to a height of about 1000 feet above the sea, in 

 incalculable numbers, especially in hot sunny places. In turning 

 over ten stones in such places, these ants are pretty sure to be 



