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year ; the nymphs of the reproductive forms require two years to 

 reach maturity. The king and queen probably live together for 

 several years, under normal conditions. The swarming of the winged, 

 sexual individuals of L. flavipes occurs in April or early May in the 

 southern States, and in late May or early June in the north. 

 L. virginicus swarms early in June, or as late as August in northern 

 Virginia, and L. lucifugus from the middle of October to April in Texas, 

 Kansas and Colorado. The distance of flight is from 75 to 100 feet, 

 but may be increased if the insects are carried by the wind. During 

 this time, they are preyed on by numerous birds, spiders, centipedes, 

 crickets, etc. Mating occurs during or after swarming, and pairing 

 takes place about a week later in the cell which marks the site of a 

 new colony, and is repeated at intervals for several years. Egg-laying, 

 in the case of newly-formed colonies of L. flavipes, begins in June or 

 July in the south-eastern States. The first egg-cluster contains from 

 6 to 12 eggs ; these are deposited in the royal cell and hatch in about 

 10 days. The larvae from the first batch develop mainly into workers. 

 The second egg-laying takes place about six months later ; sub- 

 sequently, pairing and oviposition occur at shorter intervals. No 

 types of reproductive form ever lose the power of locomotion com- 

 pletely ; hence there is no permanent royal cell and the cold season 

 is passed in the ground below the frost line. In well -established 

 colonies in northern Virginia, the period of maximum egg-production 

 is from the middle of May to September. In infested buildings activity 

 is maintained throughout the year. 



The most serious damage is that done to timbers in buildings which 

 are in contact with the ground ; living trees, shrubs, and crops are 

 rarely attacked, and then only because much decaying wood or humus 

 is present in the soil. As a rule in the United States attack on 

 foundation timber is only begun when the latter is in a moist or decaying 

 condition. In the southern United States the stems and roots of 

 cotton, maize, sugar-cane, rice, grasses and garden vegetables are 

 sometimes injured. The damage in some cases is primary, but in 

 others the plants attacked are those which have been killed by fungus 

 diseases. Nursery stock is often attacked at a scar or at the point of 

 grafting. To prevent, as far as possible, the attack on the bases of 

 buildings, the foundations should be entirely of brick, stone, or concrete, 

 without beams sunk in the ground. Complete dryness is an important 

 means of rendering buildings safe from attack. The following woods 

 are resistant to attack, owing to the presence of oils, alkaloids, gums, or 

 resins, and on account of their hardness : — California redwood, black 

 walnut, teak, peroba, mahogany, some conifers, and Eucalyptus 

 diversicolor (karri) and E. marginata (jarrah) of Australia. The 

 site of a colony is indicated by the presence of grass and earth 

 thrown out of crevices and by the point of emergence of the swarm. 

 If damaged woodwork in foundations cannot be replaced by stone or 

 concrete, wood impregnated with a 6 per cent, solution of zinc chloride 

 or a 1 per cent, solution of bichloride of mercury should be used. 

 Kerosene poured into crevices through which winged individuals 

 emerge, affords a temporary remedial measure. For poles, posts, etc., 

 coal-tar creosote is the best repellant ; for furniture, chlorinated 

 naphthaline is efiective. Wood-pulp products may be treated with 

 a solution of dihydrogen potassium arsenate or a 2 per cent, solution 



