ORDER CORRODE NT I A 81 



The must abuiulant individuals are the workers and tlien 

 tlie soldiers. Both of these forms never acquire wings. 



For this region and for the eastern and southern United 

 States there is one common species, Leucotermes flavipes 

 which is distributed as far north as the Great Lakes, to 

 Boston on the Atlantic coast, and into central Illinois in 

 the Mississippi A^alley. The colonies of this species are 

 formed, usually under old logs or stumps, and from these 

 nests the termites construct tunnels, sometimes for long 

 distances, to reach dead wood, buildings or other structures 

 in which they can secure a food supply. Porches, fences, 

 and all sorts of wooden structures sufi'er from their attack, 

 but the greatest menace, perhaps, is to wooden trestles 

 and bridges which are likely to have sudden weight thrust 

 upon them. In feeding, the ants eat out the inner part of 

 the timbers, leaving an exterior shell, thus it happens the 

 timbers are greatly weakened before any indication is seen 

 upon the surface. 



The most effective treatment is to locate the nest, give 

 it a thorough treatment of bisulphide of carbon to kill out 

 es])ecially the reproductive individuals, so that the colony 

 will not be able to multiply. 



Particularly the use of stone, brick or concrete foiuidations 

 in bridges or trestles and the separation of the wooden part 

 of structures from the earth in localities wdiere white ants 

 are present will serve as a prevention from their attacks. 

 In tropical regions the practice is to use stone or metal, 

 not only for bridges, trestles, etc., but in many places for 

 railway ties, in order to avoid loss from the termite's attacks. 



Order CORRODENTIA. 



Family Psocidae. — Book Lice. — These are small insects, 

 a considerable number of them are entirely wingless, but 

 there are many species in which the wings are fully devel- 

 oped. The wings are held in a sloping position, a somewhat 

 roof-like arrangement over the abdomen, but not folded 

 flat, and have a rather small number of veins. Their appear- 

 6 



