114 Elementary Manual of Zoology. 
the specimen. AJ] animals, including insects, can be preserved in spirit im 
this way. The method, however, is only practicable with small animals, 
and even in their case the alcohol damages the colours and renders butter- 
flies and moths almost unrecognisable. It is, however, the best way te 
preserve all caterpillars, grubs and other soft-bodied insects, also small 
snakes, lizards, fishes and other small vertebrates, To prevent the shrivel- 
ling which is liable to take place when the specimen is dropped at once 
into strong alcohol, it is agood thing to begin by putting it for a few 
hours into weak spirit, which should afterwards be changed for the very 
strongest available. 
All hard-bodied insects, including moths, are best killed in a killing 
bottle and then wrapped up in thin paper to dry, after which they can be 
preserved for any length of time, provided they are kept in a tight-fitting 
box with a little camphor, or naphthaline, to prevent their being attacked 
by mites and beetles. In the case of insects with large thick bodies, 
before wrapping them up in paper, soma of the viscera should be removed 
through a slit made with a pair of scissors on the lower surface of the 
abdomen. The abdomen should then be stuffed with a little cotton wool 
on which a few drops of carbolic acid have heen poured. For most 
butterflies no killing bottle is required, as they can easily be killed hy 
pinching the thorax between the finger and thumb. 
A killing bottle is made by putting a few lumps, each as big as the 
top of one’s thumb, of Cyanide of Potassium (which should be handled 
carefully, as it is extremely poisonous) at the bottom of alottle and then 
pouring in sufficient plaster of Paris to cover the lumps. The plaster .of 
Paris is first mixed with enough water to make it of the consistency of 
cream. The plaster of Paris soon sets into a firm mass at the bottom of 
the bottle. When it is dry, the bottle should be tightly corked up to 
prevent the escape of the vapour of the cyanide. Any insect can be 
killed in a few minutes by dropping it into such a bottle and closing up 
the eork. 
For vertebrata, which are too large to preserve entire in alcohol, the 
best thing is to preserve the skins. The skin should be removed by slit- 
ting it open down the ventral surface of the body (or, in the case of fishes, 
down one side), and then gradually dissecting it away from the body and 
limbs, using plenty of wood-ashes to prevent soiling. The skull should 
generally be left in the skin,. but it should be cleaned as much as possi- 
ble and the brain should he picked out through the large opening (fora- 
men magnum) behind. To do this the skin should be turned inside out 
over the head. The eyes also should be carefully extracted. In the case 
of small vertebrates the leg bones (in birds also the wing bones) should be 
left in the skin, but they should be cleaned as much as possible. In the 
case of fish it is a good thing to paste the whole animal up in thin paper 
