APPENDIX D. 



METHODS OF EXTERMINATING NOXIOUS ANTS. 



In houses, gardens, orchards and fields several of our imported, 

 and a few of our native ants, may become such intolerable nuisances 

 that measures must be taken to exterminate them. Merely killing off 

 their workers is, as a rule, quite ineffectual, since their place is soon 

 filled by a fresh brood reared from the eggs and larvae remaining in 

 the nest. Hence the only proper method is to destroy the whole colony, 

 and this can be accomplished only by killing the queen. But as ant 

 colonies often contain a number of queens, and as these habitually lurk- 

 in the deepest and most inaccessible portions of the nest, total eradica- 

 tion of a colony is often difficult or impossible. The usual method of 

 treatment, apart from digging up the nest completely which is often 

 impracticable consists in forcing into the nest a liquid or gaseous 

 insecticide that will permeate all the chambers and galleries and kill 

 their occupants. Our noxious ants may be divided into four groups, 

 which are here very briefly characterized, together with some of the 

 most approved methods that have been recommended for their exter- 

 mination. 



i. House Ants. The most prevalent species are Monomorium 

 pliaraonis, a small reddish-yellow ant, with well-developed eyes and 

 3-jointed funicular club ; Solenopsis inolcsto, an even smaller, more 

 yellowish species, with vestigial eyes and 2-jointed funicular club; 

 Tctramoriuin ccspitiun, the small, black or dark brown ''pavement 

 ant " and the large, black " carpenter ant," Camponotus pennsylvanicus, 

 or some of the allied varieties (C. ferruginous and noveboracensis). 

 The Monomorium, Solenopsis and Tctrainorium nest in crevices of 

 the woodwork, tiling and masonry and forage in pantries, store-rooms 

 and kitchens, where they often become a great nuisance, not because 

 they consume much of the food, but because they crawl into it. The 

 carpenter ants have similar habits and in addition sometimes do con- 

 siderable damage by weakening or destroying old woodwork in which 

 they mine their galleries. On account of their habits it is often very 

 difficult to get at the nests of these various house ants, but they may 

 sometimes be exterminated by pouring or injecting boiling water, ben- 

 zine, gasoline, or, preferably, carbon bisulphid, into the crevices which 

 they inhabit. Their numbers can often be greatly diminished by placing 



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