
INSECTS AND DISEASE 

Fig. 33. MODEL OF THE BODY LOUSE (Pediculus vestimentt) 
American Museum of Natural History 
LICE AND BED-BUGS 
Another group of insects, of great importance in connection 
with disease, is the family of Siphinculata known as sucking lice or 
Pediculide. They are small, more or less flattened, wingless para- 
sites which have an unjointed, fleshy beak barely reaching the 
thorax. The five-jointed antenne are short; the tarsi are single- 
jointed, forming a claw at the end of the tibiw; the eyes are well 
developed, convex, and distinctly pigmented. The eggs, “‘nits,’’ are 
fastened on the hair or clothing of their host. The metamorphosis 
is slight so that the newly hatched young closely resemble the adults, 
and there is no resting, pupal stage. Three or four weeks is usually 
sufficient time for these creatures to reach maturity from the time 
the egg is laid. The head-louse, Pediculus capitis, is more common 
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