APPENDIX I. 279 



lethargy too early in the spring, the critical period, no 

 doubt, of their life. For collecting caterpillars, pocket 

 tin boxes are the best receptacles. 



The satisfactory preservation of the caterpillar for 

 the cabinet is far easier than is generally supposed. 

 For anatomical purposes it is much better to dissect 

 fresh specimens, but very much may be , done with 

 specimens that have been preserved in not too strong 

 alcohol, or in glycerine and carbolic acid. For the 

 study of the markings or of the external features or 

 form, nothing equals the method known as inflation, 

 where only the pellicle and its appendages are preserved, 

 and which has the advantage of allowing the caterpil- 

 lar to be readily placed in an ordinary cabinet beside 

 the other forms of the creature's life ; also of preserv- 

 ing in their natural relations all the spines and hairs 

 which clothe the body, and of allowing these to be 

 studied at pleasure ; specimens preserved in any fluid, 

 on the contrary, are difficult to handle conveniently, 

 and their examination is unsatisfactory from the mat- 

 ting of the hairs and spines. 



The instruments necessary for inflating are a small 

 tin oven, a spirit lamp, forceps, a pair of finely pointed 

 scissors, a bit of rag, a little fine wire and a wheat 

 straw. 



The oven is simply an oblong tin box, about 2 inches 

 high, 2 inches wide, and five inches long ; the cover 

 is of glass, and one end of the box is perforated by a 

 circular hole \\ inches in diameter. The oven rests 

 upon a wire standard as in the woodcut [Fig. 194]. 

 No soldering should be used upon the oven, as it would 

 soon be melted. 



The wire 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. 195.] 



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 



