[93] COLLECTING AND PRESERVING INSECTS RILEY. 



according to the size of tlie insects. About 0.07 meter's length of a tube 

 is melted over a spirit lamp, and the tube filled three-quarters full with 

 95 per cent alcohol, the insects placed within and the contents of the 

 tube heated at the end still open, and then closed by being iDulled out 

 with another piece of glass tubing. After the glass has been held a 

 few minutes in the hand until it is slightly cooled off, the end closed 

 last is once more held over the lamp so that the points may be melted 

 together, and this end of the glass may 

 be finished. During the whole time 

 from the closure of the tube untU the 

 complete cooling of the glass it should 

 be held obliquely in the hand, so that 

 the alcohol may not wet the upper end, '^'^- 'J'^V^^ta "^ 'IZTZ^u^'^'''^ 

 for if the tube is too full it is difficult 



to melt it, as the steam quickly expanding breaks through the softened 

 mass of glass. The tube may be mounted by boring a hole through a 

 cork wStopper of the same diameter as the glass. The stopper is cut into 

 the shape of a cube, a strong insect pin put through it, and the glass 

 tube inserted into the hole. It can then be j)inned in the insect box or 

 drawer, near the imago, so that the free end of the glass may touch the 

 bottom, while the other end stands up somewhat 5 while to keep the tabe 

 in place the free end resting on the bottom may be fastened with two 

 strong insect pins. The specimens thus put up can easily be examined 

 with a lens, and if they need to be taken out for closer examination the 

 tube can be opened and closed again after a little practice." 



Preservative Fluids. — The principal liquids in which soft-bodied 

 insects may be successfully preserved are the following : 



Alcohol. — As indicated in the foregoing portions of this work, alcohol 

 is the standard preservative used for soft-bodied specimens, and may 

 be used either full strength or diluted with water. Diluted alcohol 

 should always be first used with larvse, since the pure alcohol shrivels 

 them up. The weak spirits can afterwards be replaced by strong, for 

 permanent preservation. 



Alcohol and White Arsenic. — The method of preserving insects recom- 

 mended by Laboulbene and quoted in Packard's Entomology for Begin- 

 ners, consists in plunging the insects in the fresh state into a preserva- 

 tive liquid, consisting of alcohol with an excess of the common white 

 arsenic of commerce. The larva placed in tliis mixture absorbs .003 of 

 its own weight, and when removed and pinned is safe from the attacks 

 of museum pests. This liquid is said not to change the colors, blue, 

 green or red of beetles, if they are not immersed for more than twenty- 

 four hours. This treatment is applicable to the orders Coleoptera, 

 Hemiptera, and Orthoptera. If the insect is allowed to stay in this 

 mixture for a considerable time, say three or four weeks, and then 

 removed and dried, it becomes very hard and brittle and can not be 

 used for dissection or study, but makes a good cabinet specimen. 



