I NSECT ORDERS 249 



cold. They are still used in very small quantities in hair tonics to give 

 them a stimulating effect on the scalp. 



13. The weevils. This group of beetles has jaws modified into 

 snouts. They destroy apples, strawberries, sweet potatoes, and the de- 

 veloping squares and bolls of cotton. The cotton boll weevil claims a 

 large proportion of our cotton crop each year. 



Order — Mallophaga 



These are usually called the biting bird lice, although just biting lice 

 would be more appropriate since they do not restrict themselves to birds 

 by any means. As the name indicates, they have biting mouth parts 

 with which they eat feathers, hair, or bits of skin that scale off. They 

 are wingless and have gradual metamorphosis. City people often dream 

 of accumulating a little money and retiring to a small farm and making 

 a living raising chickens. They often fail to take the lice and many 

 other bird parasites into account. It takes hard work on the part of 

 poultrymen to keep them under control. 



Order — Anoplura 



These are the true lice or sucking lice as distinguished from the bit- 

 ing bird lice and plant lice. They have strong beaks for piercing the 

 skin. The metamorphosis is gradual and they have no wings. 



1. Head louse. This louse lives on the head of man and lays eggs in 

 nits on the hairs which, when abundant, cause the hairs to stick together 

 and become matted so that the hair cannot be combed. 



2. Body louse. During World War I body lice, or cooties as they 

 were somewhat affectionately called by the soldiers, were considered 

 one of the necessary inconveniences of life at the fighting fronts. Dur- 

 ing World War II, our troops were relatively free of this parasite be- 

 cause of a vigorous "delousing" campaign with DDT, that accompanied 

 the men wherever they went. 



These lice lay their eggs in the seams of the clothing and crawl on 

 the surface of the skin, causing a tickling sensation that is quite worri- 

 some. Their great harm, however, comes from the fact that they spread 

 typhus fever. 



3. Crab louse. These lice live on the hair around the reproductive 

 organs and are often thought of as a venereal infection since they are 

 usually spread by sexual contact. 



