186 



APPENDIX. 



oven, a spirit-lamp, forceps, a pair of finely-pointed scis- 

 sors, a bit of rag, a little fine wire, and a wheat straw, or a 

 glass tube drawn to a fine point. The oven is simply an 

 oblong tin box, about 2^ inches high, 2^ inches wide, and 

 5 inches long; the cover is of glass, and one end of the 

 box is perforated by a circular hole IJ inches in diameter. 



Fig. 3.— Oven and lamp for preparing caterpillars by inflation. 



The oven rests upon a wire standard as in the woodcut 

 [Fig. 3]. No soldering should be used upon the oven, as 

 it would soon be melted. The wire for the caterpillar 

 should be very fine and annealed ; the best is that wound 

 with green thread and used for artificial flowers. It should 

 not be more than half a millimetre in diameter. [Fig. 4.] 

 Kill the subject by a drop of ether or by a plunge in 

 spirits. Then placing the caterpillar in the left hand, so 

 as to expose its hinder extremity beyond the gently closed 

 thumb and first two fingers, enlarge the vent slightly at 

 the lower edge by a vertical cut with the scissors; next 



