INSECTS 



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is hinged on to the clypeus below. The appendages of 

 the head are as follows : There is one pair of long, slender, 

 unbranched, many-jointed antennae, corresponding to the 



antennules of the crayfish. The second antennae of the 

 latter are not represented in the cockroach. The man- 

 dibles are stout, toothed structures without palps, not 

 unlike the basal parts of those of the crayfish. The 



