Preservation of Larvae 



In the first place you will need a hot-air chamber. 

 Any empty toffee - tin will serve this purpose ; one 

 somewhere about 6 inches long by 4 inches in diameter 

 will be a handy size. Get a piece of copper or soft 

 iron wire, such as milliners use ; give the wire two or 

 three turns round the tin, twisting it as tightly as you 

 can : then give the two free ends a turn or two round 

 a gas-bracket near the burner, so as to bring your tin, 

 with the open end next you, just over the burner. Or 

 you may mount the tin over a spirit-lamp, in which 

 event you will not be troubled with soot gathering on 

 the outside of your oven. You now have an oven 

 which you can make as hot as you want it by regulating 

 your flame ; you will soon discover the right temperature 

 in which to dry a skin quickly without burning it The 

 skins of small, thin-skinned caterpillars dry very quickly, 

 whilst those of large moths, such as the Oak Eggar, 

 dry more slowly even with more heat. 



Your next requirement is a glass blowpipe : this you 

 can purchase at the chemist's for a copper. Ask for a 

 glass tube about a foot long and a quarter of an inch 

 in diameter. Now, this tubing is made of a very soft 

 and pliable kind of glass, and by heating it over a flame 

 you should have no difficulty in drawing out one end 

 of the tube into a fine point, not too long and not too 

 abrupt ; the illustration (Plate VII.) will show you the 

 right length of the point. Hold the end over the gas- 

 jet, keep turning it round, and in a minute it will 

 become red and soft ; remove the end of the tube from 

 the flame, grasp it with a pair of forceps, and gently 

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