312 THE MICROSCOPE. 



having sharp points of extreme delicacy ; together forming a good ser- 

 rated edge of exactly the form given to the finest and best-made sur- 

 gical saws. In the summer-time the proceedings of this little insect 

 may be watched, and the mode of using this curious instrument seen, 

 by the aid of a hand magnifying-glass ; as they are not easily alarmed 

 when busy at this work. 



Many other insects are provided with instru- 

 ments for boring into the bark or solid wood it- 

 self. The Cynip bores a hole into the side of the 

 oak-apple, for the purpose of depositing its larva, 

 whence, as well as being comfortably lodged, it 

 receives its early food. When full grown, it eats its 

 way out of the nut ; and dropping to the ground, it 

 assumes its pupa form, which in a short time is 



fig " ' exchanged for that of the perfect fly. The most 



Female Eglantine . . . x J . 



Gall-fly and Larva, important ot these insects is the Cynip gallce tine- 



torice, fig. 143, which causes the formation of the 

 gall-nut, so extensively employed in the manufacture of ink and for 

 dyeing purposes. 



Some of the wasp tribe are very peculiar in their habits, and are 

 active agents in the economy of nature. The solitary, or mason wasps, 

 curiously construct their nests, forming cells, in which they most care- 

 fully rear their young. The social wasps, like the bees, live in commu- 

 nities, and have nearly the same divisions of labour and regulations for 

 the government of their colony. The structure and mechanical con- 

 trivance of their stings can only be seen under the microscope. The 

 stings consist of two barbed darts, which penetrate the flesh deeply ; 

 and from the peculiar arrangement of their serrated edges, their 

 immediate withdrawal is prevented ; while, by the muscular effort 

 required for this purpose, a small sack or bag near the root is 

 pressed upon, and its irritating contents squeezed into the wound. 

 After the fluid is injected, the insect possesses the power of contracting 

 the barbed points ; it then withdraws the sting from the flesh. In fig. 

 144 the sting of the wasp is shown, with its attachments and muscular 

 arrangements ; and it can be seen that the sting is most wonderfully 

 adapted to become an instrument of a very effective and deadly con- 

 struction. The brushes near it are evidently placed there for the pur- 

 pose of cleaning or wiping it. At all events this appears to be one of 

 the uses they are put to. 



The proboscis or trunk of the honey-bee next demands our atten- 

 tion ; this it uses, with its accessories, to collect the honey for its food 



