INSECTS AND WAR 5 



breakage the glass tube was enclosed in an outer 

 metal tube, and the whole was kept both night 

 and day near the body. Two meals a day were 

 necessary to keep the lice alive. When feeding, 

 the pieces of cloth, which the lice would never 

 let go of, were placed on the back of the hand, 

 hence the danger of escape was practically nil, 

 and once given access to the skin the lice fed 

 immediately and greedily. 



His success in keeping lice alive was but the 

 final result of many experiments, the majority of 

 which had failed. Lice are very difficult to rear. 

 When you want them to live they die, and when 

 you want them to die they live and multiply 

 exceedingly. A single female but recently matured 

 was placed in a test-tube, and a male admitted to 

 her on the second day. The two paired on the 

 sixth day, and afterwards at frequent intervals. 

 Very soon after pairing an egg was laid, and during 

 the remaining twenty-five days of her life the 

 female laid an average of five eggs every twenty- 

 four hours. The male died on the seventeenth 

 day, and a second male was then introduced, 

 who again paired with the female. The latter, 

 however, died on the thirtieth day, but the second 

 male survived. 



