PRESERVATION OF INSECTS. 375 



specimens on the outside of his hat, to the consterna- 

 tion of the simple Hottentots, who took him for a 

 conjuror. A more judicious plan is for a collector to 

 have the crown of his hat lined inside with cork, 

 which will save him the trouble of carrying a col- 

 lecting box. When a collector has not his boxes 

 with him, a bit of paper, twisted at each end, will 

 often answer every purpose. 



When an insect is caught, before it be placed in 

 the -collecting box or the hat-crown, it is necessary to 

 kill it, and this circumstance has given rise to much 

 prejudice, on the charge of cruelty, — the objectors 

 forgetting that most of the insects so killed could not 

 naturally survive many days,* and that their feelings 

 of pain are, in all probability, much less acute than 

 those of animals furnished with a brain, and cerebral 

 and vertebral nerves, of which they are destitute. f 

 Accordingly, a fly without its head will walk about 

 almost as if nothing had happened to it, and a wasp 

 will eat greedily with the head only when it has 

 been separated from the body. We should not like, 

 however, to be considered advocates of any species 

 of cruelty, however slight, and in killing insects for 

 a collection the speediest methods are to be pre- 

 ferred. In the case of butterflies and some moths, 

 as wefl as other winged insects, a slight pressure upon 

 the breast will instantly kill them, and exposing them 

 to heat is a still more rapid means, plunging those 

 contained in a phial into boiling water, and holding 

 those in pill-boxes near the fire. Suffocating them 

 with sulphur, as some recommend, spoils the colours; 

 and we remarked in the museums of Brussels, Lou- 

 vain, and Frankfort-on-the-Maine, that all the in- 

 sects had had their colours injured in this way, the 

 black spots on white butterflies being turned to 

 brown, and the white tinged with yellowish green. 



* See Insect Transformations, p. 347, &c. t Ibid. ch. xvik 



