'20 
On board ship, it is all-important to keep the collections from get- 
ting wet with salt-water. The papers can generally be dried at the 
galley. The whole herbarium should be exposed to the sun as often 
as possible, and frequently examined and the mould brushed off with 
a feather or camel's-hair pencil. 
I VIII. MINERALS AND FOSSILS. 
The collections in mineralogy and palaeontology are amongst all, 
those which are most easily made; whilst, on the other hand, their 
weight, especially when on a march, will prevent many from making 
such upon an extensive scale. 
All the preparation usually needed for preserving minerals and 
fossils consists in wrapping the specimens separately in paper, with 
a label inside for the locality, and packing so as to prevent rubbing. 
Crumbling fossils may be soaked to advantage in a solution of glue. 
Any fossil, whatever it be, should be collected. Minerals and sam- 
ples of rocks are also desirable. The latter should be properly selected, 
and cut to five by three inches of surface and one to two inches thick. 
Specimens ought to be tightly packed up in boxes, taking care 
that each one is wrapped up separately, in order that the angles or 
crystalline surfaces should not be destroyed by transportation ; their 
value depending upon their good condition. The same precautions 
will be required for corals. The interstices between the specimens, 
in the box or cask, may be occupied by sawdust, sand, shavings, hay, 
cotton, or other soft substance. It is absolutely essential, for land 
carriage, that no cavity be left in the vessel, or box. 
\ IX. DESIDERATA. 
As comparatively little is known of the animals and plants of the 
country west of the Mississippi and Gulf of Mexico, the attention of 
officers of the army, and others, is especially invited to this region. 
Of the fresh water fishes, trout, grayling, minnows, &c., little or 
nothing is on record ; and the same may be said of the marine species. 
The reptiles, birds, smaller mammalia (squirrels, marmots, gophers, 
pouched rats, hares, &c), and all other animals, should also be care- 
fully collected. 
This region likewise abounds in fossil bones, teeth, &c. of the 
greatest interest, especially in those portions known as"Mauvaises 
