196 



INSECT MISCELLANIES. 



into the stomach of the insect Hence, there appears 

 almost the same use of this sheath, as there is of the 

 silver pipes (canulce) used by surgeons, through 

 which they pass their lancets into parts deep seated, 

 in order to prevent their wounding any other part 

 than that which they intend to cut *." Our readers 

 will be better able to judge of the accuracy of these 

 views, by inspecting the figures below of the differ- 

 ent positions of the sheath in penetrating the skin. 



Modes of operation of the gnat's sucker. 



The mere wound, however, would not probably 

 cause much uneasiness, were it not for the insertion 

 at the same time of a sort of poisonous fluid, for the 

 purpose, as Reaumur imagined, of thinning the blood, 

 and rendering it thereby more easy to suck. If 

 this conjecture be correct, we can thence understand 

 why the pain and itching are not felt so acutely at 

 first as some time afterwards. Rogers has given a 

 * Biblia Nat. i. 157. 



