In many cases, it is very difficult to preserve the skins of larger mammals, because of the amount of arsenic required, the length of time required to keep the specimens, or the inconveniently large mass they occupy. A great obstacle in the way of making alcoholic collections on a march has been found in the escape of spirits and rubbing of specimens, and in their mixing from different localities. When more specimens are to be added, some of the air can be released and the bag is then re-inflated.
Much attention should be paid to obtaining many specimens of various species of small fish, commonly known as whiting. The Zygonectess swims slowly along the surface of the water, the tip of the nose usually exposed.
LIST OF APPARATUS USEFUL FOE TRAVELLING PARTIES
- Two WOODEN chests; OR TWO LEATHER PANNIERS supplied with back strap for throwing across a mule, when the transporta-
- Pencils for marking the bags,
- Fishing-line and hooks
- A BALL OF STOUT COTTON TWINE
- A SHEET OF PARCHMENT
- Geological hammer
- Double-barrelled gun and rifle; also shot-belt, powder-
- Cork-lined boxes
- IMPLEMENTS FOR SKINNING
- PRESERVATIVES
All facts relating to the habits and characteristics of the different species of animals, no matter how trivial and commonplace they may be. Two COPPER KETTLE in one of the cases or chests, to hold the alcohol for specimens requiring this method of preservation, namely: Reptiles, fish, sometimes birds, small quadrupeds, most insects, crabs and all soft invertebrates. These are intended to be inflated in the kettles and displace by the alcohol, allowing it to rise to the edge of the copper cap and thus be filled.
These are mainly intended to separate samples from different localities from each other; and in the second place, to secure them against both^. All mammals, fish and reptiles longer than five or six inches must have a small incision in their abdomen to facilitate alcohol intake. The skin covering the abdomen in mammals should always be loosened so that it does not adhere to the abdominal walls to prevent hair loss.
All notes of habits, etc., must be made in the notebook; but the date, locality and gender must be marked in addition to the specimen's label. By means of a loop at the other end the string may be suspended to a post or awl, which, when the hook is inserted into the body of an animal, will give the free use of both hands in skinning. The best material for preserving skins from animals consists of powdered arsenic acid or the common arsenic of the shops.
This is composed of the following ingredients: arsenic 1 oz.; white soap 1 oz.; potassium carbonate1 drachma; water 6 drachmas; camphor2 drachmas.
III. SKINNING AND STUFFING
BIRDS
A recent writer recommends that the girth of the bird be taken before skinning, by means of a band of stiff paper passed round the middle of the body above the wings, and fastened in the form of a ring. After these initial measures, make only one incision through the skin, from the lower end of the sternum to the anus. When making the first two cuts, be careful not to damage or cut the zygoma, a small bone that extends from the base of the upper mandible to the base of the mandible.
The cloth should be applied as soon as the edges of the first cut are raised, enough to be enough. The next operation is to connect the two wings inside the skin with a cord, which must be passed between the lower ends of the two bones forming the forearm, before how- . ever cut off a piece of an arm if it still holds. Remove any muscle and fat that may cling to the bottom of the tail or skin, and apply plenty of preservative wherever possible.
Begin by opening the mouth and putting cotton in the trachea and upper part of the throat until these parts have their natural shape. Then take tow or cotton, and after making a roll rather less thick than the original neck, put it into the skin and press firmly into the base of the skull. Then pull the head out again, and make an incision on the outside, along the back of the skull, skin the head.
Some writers advise a very careful cleaning of the skull without cutting away any of the bones, so that the skin, if otherwise useless, will at any time furnish a skull for an osteological series.
MAMMALS
The sex of the specimen can be determined after hatching by making an incision in the back of the vertebrae and exposing the inner surface of the "small of the back". The generative organs will be found tight to this region (almost opposite the last ribs), separating it from the viscera. The testicle of the male will be observed as two spheroidal or ellipsoidal whitish bodies, varying with this season and species, from the size of apin's. However, it takes so much more time that it can hardly be done on a trip, and a skull is generally better obtained from another monster, perhaps too much shot to be skinned.
Probably none of these remedies, including ether, chloroform, and turpentine, will kill the larvae; they may repel the perfect insect, but when the eggs are laid there is not much remedy, except to expose the skins to a temperature a little lower than boiling water for twelve hours, and the Q^g or particles are thus dried. Therefore, the best plan will be to keep the skins clean and not packed too tightly.
REPTILES
23 with either sand or sawdust, by the use of which their shape ia
FISHES
Nevertheless, they may be nsefnlly skinned and form collections whose value is not commonly appreciated. Sharks, skates, sturgeons, garpikes or garden plaices, muds, and all those belonging to the natural orders Placoides and Ganoids, should undergo the same process as above for birds, mammals, and reptiles. Then the skin is removed from the meat, the fins are cut at their bases under the skin.
Fins may be expanded when wet, on a piece of stiff paper, which will keep them sufficiently stretched for the purpose. To accomplish this, lay the fish on a table with the left side up; the oneitis intended to preserve. Spread out the fins by placing a piece of paper under each one, to which it will stick when dry.
When the threads are dry, turn the fish upside down, cut with scissors or scissors around the body, just inside the ventral and back lines, from the top and back of the head, along the back to the tail, along the base of the caudal fin. Thus, separate the entire body from the left side of the skin, starting from the tail. When you are close to the head, cut the body, with the right ventral and pectoral fins, and proceed by making a section of the head and removing almost half of it.
Cut a round piece of black paper the size of the track and place it close to the pupil.
25 skin and fix it on a board prepared for that purpose. Pin or tack
1 . GENERAL REMARKS
VERTEBRATES
Smaller and more delicate specimens may be placed in vials or bottles and packed in larger containers with other specimens.
INVERTEBRATES.*
V. EMBRYOS
Sea urchins and starfish can be dried by first immersing them in boiling water for a minute or two and wrapped in cotton or any soft material you can use. Insects without wings, such as spiders, scorpions, centipedes or millipedes, earthworms, hairworms, and generally all worm-like animals found in water, should be preserved in liquor. They should be collected each time they are encountered and in any number obtainable for each type as they are always in demand for exchange purposes.
Hundreds of eggs of all kinds with their nests (or without, when none are found) will be gladly received. Eggs, when fresh and before the chick is formed, can be emptied by making small pinholes on opposite sides and blowing or sucking out the contents. It is always better to wrap each egg in a loose layer of cotton before layering, and they should be packed in small wooden boxes.
Cracked eggs should have strips of tissue paper pasted over the break line; or the crack can be painted over with collodion while the sides are pressed together. The eggs of fish, salamanders and frogs can be stored in spirits and stored in small vial sorbents.
YII. PEEPAEATION OF SKELETONS
After all this is removed and the pit of the bones is scrubbed with water with a stiff brush, they should be soaked a little more. Ligaments, according to Eyton,* may be converted into a hard leathery substance by being immersed in a liquid prepared by making a saturated solution of common alum, and, when cold, diluting it with a quantity equal of water, and adding half an ounce of common salt to every half pound. Ether should be kept in a tight jar, and every precaution taken to prevent unnecessary exposure to light or fire, as the vapor is extremely explosive.
33 needed. The specimens as gathered may be placed in a tin box,
Fruits of this type should be numbered to match the pattern and stored in saddles or elsewhere. On board a ship, it is very important to prevent the collections from getting wet with salt water. The entire herbarium should be exposed to the sun as often as possible and inspected frequently, and the mold should be removed with a feather or camel hair pencil.
When collecting algae, corals or branching, pink or calcareous corals, care should be taken to remove the entire specimen with the base or root. Rough types can be air-dried (but not in too much sun) and turned occasionally. The more sensitive species should be brought home in salt water and carefully washed in fresh water, then transferred to a shallow pool of clean fresh water and floated out.
A piece of white paper of the appropriate size is slid down and gently lifted out of the water with the specimen on top.
IX. MINERALS AND FOSSILS
X. MINUTE MICROSCOPIC ORGANISMS
Pass a quantity of the water, varying with its turbidity from half a liter to agile, through the paper, and allow it to dry. Mark the paper or its envelope with the amount of water passed through, date, place, etc. It is desirable to have copies thus made for all localities and for each month of the year.
They can be sent, as well as light packages of dried mud, etc., by post and should be sent as quickly as possible. Classification.— The animals living in the sea, except fishes and other vertebrates, may for convenience be divided into groups as follows: 1. It is necessary, however, to survey the whole range, as each species has its own special arrangement, and many forms can live only where they are exposed to the air most of the time every day.
But few specimens will be found on the surface of such ground, though the small pools lying on it, with the dip-net for shrimps, &c. must be scooped up, but it is only by the count that his true wealth can be developed. Weedy ground is so called from the abundance of eelgrass and seaweed that covers it. Where there are stones, especially flat-colored ones, about large enough to afford a moderate degree of exercise to an ordinary man in turning them over, there the zoologist can never fail to fill his basket and bottles for under these stones, dozens of rare and beautiful species withdraw for moisture and protection during the retreat.
Investigations of the littoral seashore should be carried out not only in bays, inlets and creeks, but on the beaches of the ocean, in every locality, to get a true idea of its fauna, such as the corresponding animals.
39 and these can only be obtained with certainty and facility by means