98 INSECTS &BBOAD. 



If examined with a Ions, the soft and almost velvety surface 

 of the head and thorax is seen to be caused by an innumerable 

 multitude of very minute projections or pustules, all perfectly 

 circular, and placed just so closely together as to allow a small 

 ring of level surface to be seen round each of them. "When 

 viewed with light that falls directly upon the surface, these 

 rings appear to be not circles, but hexagons, just like the lenses 

 of the insect's compound eye, or, to use a familiar example, 

 like those glass tumblers whose outer surface is covered with 

 small hemispherical knobs. The elytra are smooth to the naked 

 eye, but under the lens they are seen to be profusely covered 

 with very small punctures. 



The female has remarkably small jaws, which, as well as her 

 head, are covered with large and deep punctures. As her head 

 has not to support such enormous jaws as those of the male, it 



Fio. 45.— Cladognathus giralfa. Female. 



is small in proportion to the jaws, and in consequence gives her 

 an aspect very unlike that of her formidable mate. 



There is no species of Lucanidse in which the variation in the. 

 jaws of the fully and partially developed males is so marked as 

 in this insect. In the collection of the British Museum there is 

 a fine series of specimens, showing an amount of variation which 

 would make anyone but an experienced entomologist believe 

 that insects so different in size and shape must belong to dif- 

 ferent species. Indeed, as we shall presently see, many such 

 varieties have actually been described and figured as different 

 species. In one of these small males the jaws are not half as 

 large as in the fully developed insect, and the boldly branch- 



