4 BULLETIN 333, IT. S. DEPARTMENT OP AGRICULTURE. 



swarm is usually in early June or later in the summer. The soldier is more 

 slender than in flavipes, 4.5 to 5 mm. in length, the head being twice as long 

 as broad. 



In certain localities where several species of termites are known 

 to occur the injury herein described can not always be attributed to a 

 definite species, since specimens of the insects were sometimes not 

 taken. This is particularly the case in the Southwestern and Gulf 

 States and on the Pacific coast. It is probable that species not pre- 

 viously recorded as injurious will be found to be injurious, and 

 it is known that undescribed species or those new to science occur. 



COMMUNAL ORGANIZATION AND LIFE. 



SITUATION OF THE COLONIES OR NESTS. 



In North America termites do not construct large permanent nests 

 of earth or mounds above ground, as in the Tropics. They make the 

 nests in the wood of dead trees, decaying logs, or stumps in the for- 

 est ; or in the foundation timbers of buildings, fences, or other struc- 

 tures of wood in contact with the ground ; or in a labyrinth of under- 

 ground passages in the earth, usually underneath wood or other 

 vegetation. These nests are not as permanent as the mound nests, 

 since the species have wandering habits and there are seasonal 

 changes in the colony life. These species of termites (Leucotermes 

 spp.) are essentially wood destroyers; their excavations usually 

 follow the grain in solid wood. A protective outer shell of wood 

 is always left intact by these blind, soft-bodied insects. Termites 

 infest buildings by means of tunnels through the ground to and up 

 through the foundation timbers, or, in case of foundations of stone 

 or other impenetrable material, cover their pathway by means of 

 " sheds " constructed of earth and excrement over the surface to the 

 woodwork. Termites sometimes inhabit and enlarge the burrows of 

 various other wood-boring insects. 



SEASONAL VARIATIONS IN THE COLONY. 



The center of activity in termite colonies changes with the seasons, 

 due to varying needs as to conditions of warmth and moisture. In 

 the eastern United States, in spring, when there is abundant mois- 

 ture, outlying galleries of colonies are teeming with life, where, dur- 

 ing the heat of summer, conditions would be too dry. In arid regions 

 termites burrow deep into the ground ; consequently in summer they 

 bury themselves more deeply, going into the less exposed galleries. 

 In the late autumn or at the beginning of winter (in northern Vir- 

 ginia, late October or early November) they enter the ground and do 

 not come above ground till late in February or early March. Again, 

 the colony readily migrates and the site is abandoned if conditions 



