MICROSCOPIC OBJECTS. 



41 



The whole of this formidable apparatus is composed 

 of six parts, (exclusive of two guards or feelers,) all of 

 which are inclosed in a fleshy case, which in the figure is 

 totally removed, as it contained nothing remarkably 

 different from that of other insects with two wings. 

 The guards or feelers are of a spungy or fleshy sub- 

 stance, and are grey, covered with short hairs ; they 

 are united to the head by a little joint of the same 

 texture. These guards are a defence to the other parts 

 of the apparatus, as they are laid upon it side by side 

 whenever the animal stings, and by that means pre- 

 serve it from external injury. The two lancets, B B, 

 evidently open the wound, and are of a delicate and 

 tender structure, formed like the dissecting knife of the 

 anatomist, with a sharp point and slender edge, but 

 gradually increasing to the back. The two shaped 

 instruments, c c, appear as if intended to enlarge the 

 wound, by irritating the parts round it ; to accomplish 

 which, they are jagged, or toothed; they may also 

 serve, from their hard and horny texture, to defend 

 the tube E, which is of a softer nature, and tubular, to 

 admit the blood and convey it to the stomach ; this 

 delicate part is inclosed in a case, D, which entirely 

 covers it. 



The eyes of insects are singu- 

 larly constructed, but this struc- 

 Fig. 4. ture is not discover- 

 able without the 

 assistance of the mi- 

 croscope ; the eyes 

 of the libellula are 

 hexagonal, as seen 

 in the accompanying figures, 

 3 and 4. 

 Figures 5 and 6 present a leg of the Leucospis Dor- 



Fig. 5. 



Fig. 3. 



