10 ON CUTTING SECTIONS OF THE EYES OF INSECTS, &C. 



instrument, which I propose calling the Quekett Section Cutting 

 Machine (if it finds a place in your favour), and others. All I 

 need say on this point is, that it may fairly be left to the opera- 

 tion of the law of " natural selection," as to which being the 

 weakest shall go to the wall, for doubtless the fittest will survive. 



EXPLANATION OF PLATE.— I. 

 Fig. I. 



a. The adjusting screw for regulating the thickness of the sections. 



b. The main or traversing screw moving the slides. 



c. The cutter. 



d. d. d. Guide pulleys for carrying the string to the cutter pulley. 



e. Small frame for supporting the object. 

 x. Cutter frame moveable on its pivots. 



Fig. IT. 



Sectional view of the object-frame. 



e. Frame as in figure 1 capable of motion on its pivot horizontally. 



f. Brass piece also capable of motion on its pivot (p) and faced with, 



g. A piece of cork. 



h. The head or object. 

 c. The cutter. 



