14 
It is sometimes necessary to guard against the theft of spirits em- 
ployed, by individuals to whom the presence of reptiles and fishes in the 
liquor is no objection. This may be done by adding a small quantity 
of tartar emetic, ipecacuanha, quassia, or some other disagreeable sub- 
stance. The addition of corrosive sublimate will add to the preserva- 
tive power of the spirit. 
Should the specimens to be packed vary in size, the largest should 
be placed at the bottom. If the disproportion be very great, the deli- 
cate objects at the top must be separated from those below, by means 
of some immovable partition, which in the event of the vessel being 
inverted will prevent crushing. The most imperative rule, however, 
in packing, is to have the vessel perfectly full of something, any 
vacancy occupied only by air exposing the whole to the risk of loss. 
In carrying specimens in liquor when travelling, an almost insuperable 
difficulty is found in preventing rubbing, owing to the necessity of 
leaving enough space for the addition of specimens. This danger 
may be obviated by introducing an India-rubber, or oiled silk bag or 
bladder, provided with a valve, and blowing it up enough to fill the 
unoccupied space. 
It often becomes a matter of great importance to separate the speci- 
mens of one locality from those of another, in the same vessel. This 
may be readily done by having a number of small bags made of mos- 
quito net stuff, lino, or other porous material, and from six to twenty 
inches long, by two to six wide. They are made like pillow-cases, 
open at one end, and sewed around the other three edges with coarse 
stitches. The specimens, on being gathered, may be put into a bag 
of proper size, and the mouth closed by tying a piece of thread. A 
number may be marked on the bag with a pencil, or with ink on a 
parchment label, placed inside or tied to one corner. These bags are 
of incalculable service on a march, or in transporting collections, the 
individuals of which are to be kept separate for any purpose whatever. 
2. VERTEBRATA. 
Fishes under six inches in length need not have the abdominal 
incision. Specimens with the scales and fins perfect should be selected, 
and, if convenient, stitched or pinned in bits of muslin, &c, to pre- 
serve the scales. In general, fishes under twelve or fifteen inches in 
length should be chosen. The skins of larger ones may be put in 
liquor. It is important to collect even the smallest. 
