rHYSIOLOGY OF INSECTS. 129 



CHAPTER V. 



OP THE CHARACTERS OF SURFACE. 



470. The exterior or bony shell of insects, is 

 very various in the character of its surface ; and 

 as these variations are constant, or pretty much 

 so, in the same kind of insect, a correct know- 

 ledge of the terms employed in distinguishing 

 them is very essential. 



471. The variations of surface are of two kinds : 

 form of surface, called also sculpture ; and colour 

 of surface. The terms employed to describe these 

 are mostly from the Latin; a language which 

 affords great facility in defining slight distinctions. 



472. The variations of form are many ; most 

 of them are described by terms universally under- 

 stood ; as convex, concave, flat, rough, smooth, 

 shining, &c. ; others require elucidation. 



473. Levigate {levigatus), is when the surface 

 is perfectly free from elevations, or depressions of 

 any kind. 



474. Glabrate (gluber), is when it is brilliantly 



