460 THE TIGER BEETLE. 



entirely of a substance called chitine, to which are added several other materials, such 

 as animal matter, albumen, and the oil which gives the bright colors so prevalent in 

 most of the species. 



There are many other interesting points in the structure of the Insects, such as the eyes, 

 the wings, the tracheae, etc., which will be described in the course of the following pages. 



The systems on which the Insects have been arranged are as perplexing as numerous, 

 differing according to the characteristics chosen by their authors. In this work the 

 system employed is that of Mr. Westwood, which seems to combine many advantages 

 to be found in the different arrangements of various authors, and is sufficiently intelli- 

 gible to be understood without any painful exercise of the memory. 



The first order, according to this author, is called the Coleoptera, a word of Greek 

 origin, signifying sheathed-winged animals, and includes all those insects which are 

 more popularly known under the title of Beetles. In these insects the front pair of wings 

 are modified into stout horny or leathery cases, under which the second pair of wings 

 are folded when not in use. The hinder pair of wings are transparent and membranous 

 in their structure, and when not employed are arranged under the upper pair, technically 

 called the elytra, by folds, in two directions, one being longitudinal and the other 

 transverse. On examining these wings carefully it will be seen that their supporting 

 nervures are furnished with hinge-like joints, which permit them to be folded in the 

 right direction and no other. One of the best examples of a folded wing among the 

 beetles is to be found in the common Cocktail Beetle (Stapkylinus), where the large 

 and beautiful wings are packed away under two little square elytra, just as a folded map 

 is packed into its covers. In other instances where the elytra are very long, as in the 

 common Musk Beetle (Cerambyx), the wings are first folded longitudinally and then 

 a little piece doubled over at the tip, so as to fit within the cover. 



The mouth is furnished with jaws, often of considerable power, which move 

 horizontally. 



The last character that must be considered in the beetles is the mode of the meta- 

 morphosis or change of form which is undergone by them before they attain their 

 perfect state. After being hatched from the egg they take the form that is popularly 

 known under the title of grub, and is quite unlike the shape of the perfect insect. In 

 this state they remain for various periods according to the species and the climate, and 

 then pass into the second, or pupal state, when they look much like the perfect insect, 

 but are unable to move about. This characteristic seems to separate them from the 

 earwigs, cockroaches, and grasshoppers, which would otherwise have been included in 

 the same order with the beetles, but are now placed in separate orders on account of 

 the character of their preliminary stages, where the shape of larva, pupa, and perfect 

 insect are very similar, and the pupa is active. 



The reader must not imagine that in every insect which may be classed among the 

 beetles he will find all the organs which have been mentioned, for in many cases they 

 seem to be entirely wanting. The female glow-worm, for example, has no wings at all ; 

 and in many genera the second pair of wings are wanting and the elytra fused together 

 at the edges. Still, in most instances the organs, or, at all events, the indications of 

 their existence, can be found ; while the character of the metamorphosis will always 

 settle the true rank of an insect whose position seems doubtful. 



Passing over, for the present, the details of classification, we come to the first family 

 of insects, scientifically called the Cicindelidae, and popularly known by the name of 

 Tiger Beetles, or Sparklers, both names being very appropriate ; the former on account 

 of their exceeding voracity, their ferocious habits, and the wonderful activity of their 

 movements ; and the latter in allusion to the brilliancy of their colors as they flash 

 along in the sunshine. These Beetles are represented by several British species, among 

 which the common TIGER BEETLE (Cicindela campestris) is the most common, and 

 perhaps the most beautiful. Well does this little creature deserve its popular name, 

 for what the dragon-fly is to the air, what the shark is to the sea, the Tiger Beetle is 

 to the earth ; running with such rapidity that the eye can hardly follow its course ; 

 armed with jaws like two reapers' sickles crossing each other at the points ; furnished 

 with eyes that project from the sides of the head and permit the creature to see in 



