Biological specimens are important basis and basic data for studying and discussing biological morphological structure and ecological characteristics. It is true in shape, complete in structure and lifelike. Can be preserved forever. Therefore, for a long time, it has been used not only by biologists for scientific research, but also by people for appreciation and collection, and is known as a "living cultural relic" and antique in the history of human development. The biological specimens of some rare animals and plants are facing extinction, and their value is incalculable, which has become a rare thing for people to study and collect. Judging from the interest in specimen making, students have a strong interest in it. However, when making vertebrate specimens, it is difficult for students to peel and preserve them by traditional methods. So we can make some improvements.

When peeling, the traditional method is to make an incision in the abdomen. First, the skin and muscles at the tail of the hind limbs are separated from the back, and then the skin and muscles of the forelimbs and the head are separated forward to the nostrils, and the skull is preserved, cut off at the foramen magnum, and the body is taken out from the opening of the abdomen. Because the whole body is large and the opening cannot be too big, it is very difficult to operate in the peeling process, especially for students, it is easy to break the skin and expand the opening. This will directly affect the suture of the opening and the beauty of the specimen. The method of sectional stripping is adopted here: after an incision is made in the abdomen, the skin and muscles of the abdomen and back are separated first, and then the body is cut into two parts from the abdomen. Then peel them forward and backward respectively. This greatly simplifies the operation, especially for larger and longer animals such as snakes and lizards.

In addition, in anti-corrosion treatment, traditional preservatives are generally made of arsenic and some anti-corrosion drugs, such as;

Arsenic (2 parts)+alum powder (7 parts)+camphor powder (1 part)+glycerol (a little)

But arsenic is toxic and dangerous to operate, especially for students. So we can prepare a non-toxic preservative:

Boric acid powder (130 parts)+alum powder (7 parts)+camphor powder (60 parts)+glycerin (a little), preservative, good antiseptic effect, non-toxic and safe operation. Suitable for handicrafts, specimen making and home decoration, especially for student specimen making.

It is easier and safer for students to use the improved method to make specimens. At the same time, there are some details in the production, which we can decide according to the production of different specimens. We take making bullfrog specimens as an example for concrete analysis.

First of all, bullfrog can be executed: air injection method and suffocation method can be used, and suffocation method is the best.

Then peel it off, cut off the limbs outside the ankle bone according to the subsection peeling method, and keep the phalanx (the muscles on the phalanx should be cleaned). The head is cut off from the foramen magnum (the head muscles should be cleaned). In addition, it is necessary to remove the brain tissue in the cranial cavity (make a hook with iron wire, extend into the cranial cavity from the foramen magnum and mash the brain tissue out).

After peeling, don't smoke and fill it immediately. Should be soaked in 75% alcohol 1-2 days. Because bullfrog skin has a lot of mucus and grease, it will rot easily in the future. Soak in alcohol to remove fat (some amphibians and reptiles such as frogs and lizards can do this). 1-2 days later, take it out of the alcohol and apply a non-toxic preservative on the inside of the skin (see above for the formula). The iron wire is used as a bracket, which is fixed in the bullfrog body, and the front end is fixed at the foramen magnum (the iron wire is hooked into the cranial cavity, and the cranial cavity is filled with cotton coated with preservatives, which is beneficial to fixation and anticorrosion). The steel wire supports of the limbs pass through the palm and are fixed.

When filling with cotton, pay attention to filling around the bracket and wrapping the bracket in the middle. Filling and molding, making it into the natural shape of bullfrog. Finally, the bullfrog is fixed on the bed board and fitted with artistic eyes. Made a beautiful bullfrog specimen. Can be used for teaching and scientific research, and can also be used for decoration.

From the process of making vertebrate specimens, I deeply realized that we should dare to break the tradition and innovate, and find some methods that are easier for students to accept and master, so that they are more interested in learning and easier to master.