There are many kinds of arthropods in the ocean, and their specimens are also soaked and dried. Large shrimps, crabs and crabs can be dried by injecting 1% formalin into animals, then soaking in 1% formalin solution for 6-1 hours, and finally drying in the sun. Immersion method: First put the animals into fresh water to kill them, then put them into 7% alcohol to preserve them. In order to prevent the limbs of the specimens from being crisp, it is best to add a few drops of glycerol. Echinoderm sea cucumber should be anesthetized before fixation. The collected sea cucumbers are cultured in a container filled with seawater for several days, and after their tentacles are fully extended, menthol is removed from the water surface, and a small amount of magnesium sulfate is added. It can be stored in 7% alcohol when the tentacles are touched by a dissection needle and no longer contract. The method of making starfish specimens is the same. Some sea urchins can be anesthetized in fresh water and then stored in 7% alcohol. When fixing, a small hole can be pierced on the back or ventral side, so that alcohol can quickly soak into the sea urchin. In addition, sea urchins and starfish can also be made into dried specimens. The procedure is to shape the animals first, then soak them in 1% formalin solution for 6-12 hours and dry them in the sun. The preparation of fish immersion specimens is relatively simple. First, the sediment, mucus, mouth and gills on the body surface are cleaned with clear water, and then the fins, spines and fins are spread out and stored in 1% formalin. This kind of specimen is limited to smaller fish. If it is a large fish with a body length of several meters or even more than ten meters, it is necessary to make a peeled specimen. The procedure of making peeled specimens is as follows: first, measure and record the necessary data of fish body length, total length, maximum body circumference and minimum body circumference, and then draw a drawing. After these jobs,

cut the belly of the fish with a knife along the midline of the belly, carefully peel off the skin of the fish, and remove the eyeballs and gills. After the skin is separated from the body, further remove the meat and fat from the skin, and soak the skin in 7% alcohol for several days. In the meantime, we began to make a prosthesis slightly smaller than the fish body with wooden boards and strips according to the measured data and sketches. After the prosthesis is made, in order to make it soft and hard, it is necessary to apply straw to the prosthesis and put a sack on it. Finally, the fish skin is taken out of the alcohol, and a preservative is coated on the inner surface of the fish skin (formula: 5g of acid, 15g of soap, 3g of brain stick, mixed with water, boiled with slow fire, and can be used in paste), and then it is put on the prosthesis for suture, and the shape is arranged, and each fin is patted flat and fixed with a wooden board for a period of time. After drying, remove the board and install the glass eye in the eye socket, and it will be finished. These specimen making methods are not complicated, and it is easy to succeed as long as you are careful and patient. In order to make a specimen of stigma worm, chordates need to be cultured in sea water first, and then they are anesthetized with fresh water and put into 7% alcohol semen after the sediment in their abdomen is discharged. After collecting the sea squirts, wash them with clean water, put them into the sea water to spread them out, and put them into menthol for anesthesia after the outlet and inlet holes are opened. When the outlet and inlet holes are no longer closed, they can be preserved with 5% formalin solution. Molluscs There are many kinds of marine mollusks, and their life styles are also different. Molluscs can be soaked or dried. Dry specimens are mostly limited to the types of shells, such as tiger-spotted baby, egg snail and red snail, which can be killed in fresh water and left to rot.