NATURAL HISTORY. 
103 
investigated. In the cases, however, of recent alluvial strata or the sup¬ 
posed beds of ancient lakes, or deposits in caves, or raised sea-beaches 
containing shells or bones of vertebrate animals, the traveller will do 
well to bring away specimens if a good opportunity offers. If the plan 
of the expedition includes the collection of fossil remains, the traveller 
will, of course, provide himself with a proper geological outfit, and obtain 
the necessary instructions before leaving Europe. (See Section III.) 
General Remarks .—All collections made in tropical countries should be 
sent to Europe with the least possible delay, as they soon become de¬ 
teriorated and spoilt unless great care be bestowed upon them. Dry skins 
of animals and birds may be packed in wooden cases well lined and 
padded with brown paper. Shells and skulls should be provided with 
abundance of elastic padding, such as cotton. Boxes containing pinned 
insects and Crustacea should be packed within larger boxes and sur¬ 
rounded by an ample bed of hay or other light dry elastic material; un¬ 
less this last point is carefully attended to, it is doubtful whether such 
collections will sustain a voyage without more or less serious injury. 
Observations of Habits , &c .—Travellers have excellent opportunities of 
observing the habits of animals in a state of nature, and these f Hints J 
would be very deficient were not a few remarks made upon this subject. 
To know what to observe in the economy of animals is in itself an accom¬ 
plishment which it would be unreasonable to expect the general traveller 
to possess, and without this he may bring home only insignificant details, 
contributing but little to our stock of real knowledge. One general rule, 
however, may be kept always present to the mind, and this is, that any¬ 
thing concerning animals which bears upon the relations of species to 
their conditions of life is well worth observing and recording. Thus, it 
is important to note the various enemies which each species has to con¬ 
tend with, not only at one epoch in its life, but at every stage from birth 
to death, and at different seasons and in different localities. The way in 
which the existence of enemies limits the range of a species should also 
be noticed. The inorganic influences which inimically affect species, 
especially intermittently (such as the occurrence of disastrous seasons), 
and which are likely to operate in limiting their ranges, are also im¬ 
portant subjects of inquiry. The migrations of animals, and especially 
any facts about the irruption of species into districts previously unin¬ 
habited by them, are well worth recording. The food of each species 
