C10

A bald stone appeared in front of his eyes, and footprints of various sizes appeared on the soil beside it. The footprints were messy, crooked, and looked very messy. It seemed that someone must have been inside this cave before. Shen Yuan felt a burst of happiness in his heart, he felt that he has hope of walking out of the cave. After carefully observing the soil on the ground, Shen Yuan discovered a clear trace, as if it was left behind by a heavy object being dragged on the ground until it reached a place with water. Only then did the trace disappear. Unexpectedly, Shen Yuan found a small bamboo chopping block by the water side, tied with hemp rope, tied to a wooden stake on the shore. There was a long bamboo shoot on the bamboo chop. After untying the hemp rope, the bamboo shoot would spin with the rapidly flowing water, pushing the bamboo shoot into the water and moving towards a place full of green vines.

When Shen Yuan rode the bamboo shoot to where the vine was, as long as he pushed the vine to the side, the boat would be out. In the blink of an eye, it was already on top of a river outside. It turned out to be a cave entrance, hidden in the dense vines hanging down from the cliff above.

Shen Yuan raised his head and looked at the mountain opposite him. It was like an isolated island.

Could it be the Bird Island ahead?

The bamboo row moved forward in the torrent. The river was not very deep. Through the clear water, one could even see the pebbles at the bottom of the river and the aquatic plants floating in the water.

The bamboo shoot finally docked. It was only when he saw tourists walking around that Shen Yuan was sure he had come to Bird Island.

Grass, vines, and low shrubs lined both sides of the path, crisscrossing each other and covering the island in early spring. Walking along the green path, I could barely feel the cold spring air.

The shape of the bird island, the twists and turns of the Lai River, and the enigmatic route of the Goose-Ridge Ditch all of a sudden gave Shen Yuan an epiphany on the characters in Su Heshan's diary. The four letters were indeed related to Su Heshan's plan to take a picture of the terrain. However, Shen Yuan still did not know if this had anything to do with Su Heshan's murder.

After that, Shen Yuan went to the Public Security Technical Unit in the City of Lai and explained his identity. After completing some formalities, he took a photo of the maggots soaked in alcohol bottles and brought one back to the school.

Ding Wei's car drove up to the entrance of the Central South University School of Medicine. A youth with green pants and a black leather jacket walked towards him. His hair was slightly curly, his face was dark red, and a smile hung at the corners of his mouth.

"Are you Professor Xu's doctoral student, Shen Yuan?"

The Professor Xu that Ding Wei mentioned was Xu Zhijian from the Department of Forensic Medicine of the Southern Medical University. He had cooperated with Ding Wei in solving some important cases.

Shen Yuan nodded his head.

"You're looking for me?"

Shen Yuan explained the whole incident of his girlfriend Su Heshan's death to Ding Wei.

"You mean the length of the maggots on the corpses is abnormal?"

"Indeed."

"What does that mean?"

"The average temperature in Hunan at the end of February should not exceed twenty degrees Celsius. It should not grow to one millimeter long on Su Heshan's corpse within two days."

"Wait. According to your mentor, the topic of your doctoral thesis is how do you use insects to deduce the time of death? " Ding Wei asked.

"Yes."

"So, how does your research help in deducing the time of death?"

"Using entomological knowledge, the time of death, place of death, cause of death and other facts can be analysed and determined. To be specific, different areas usually had different species of flies, so the maggots that appeared on the corpse would also change depending on the location of the body. In addition, the growth cycle from spawning to becoming a maggot has a certain regularity, which is also related to the environment and temperature. Forensic entomology is based on the species and growth pattern of flies on the corpse to determine whether there has been a removal of the body or to infer the time of death. "

"Well, it sounds good." Ding Wei said, "However, it seems that there has been no case of using insects to solve cases. Why are you interested in this? "

Shen Yuan slowly said, "My teacher had an idea about forensic entomology since a long time ago. I was the first doctoral student to put his idea into practice. My undergraduate degree is botany, my graduate student is biochemistry, and I took a few medical courses while I was a doctor. After the doctor graduated, I didn't expect that the Institute of Forensic Medicine of the School of Medicine of Central South University would be recruiting someone with a background in forensic insect knowledge. That's how I got into this business. It can be said that I am not interested in choosing insect forensic medicine as my future scientific work, but I just happen to have such a position. "

"So, when insects appeared on your girlfriend's body, you thought of your research?" Ding Wei said, "This is in the wilderness, not in your warm room. By controlling a certain temperature and humidity, the insect activity in the room is clearly regular, but in the wild it is completely different. "

"I know. When I found the fly's insect on Su Heshan's body, I was taken aback. Judging by the temperature of the area and the environment, it was unlikely that such a length of fly larva would appear on the corpse in such a short time. "

"Do you think there should not be maggots of this length on Su Heshan's corpse?"

"Yes, from the time of his death to his discovery of the corpse, only two days or so has passed. It's indeed somewhat inconceivable."

"Is there a special species of insect that you haven't discovered yet?"

"Although I haven't been able to determine what kind of insects are on Su Heshan's body, based on my knowledge of the various regions in the country, they should be maggots belonging to flies. There were many kinds of flies, and it was certain that it was unlikely that any of them would produce such a length of larva on the victim's body during the two days of climate in that part of Bird Island. Police investigation records show that Su Heshan was killed on board the ship. If there were no other animal carcasses on board, it would be an exaggeration for insects to lay eggs on the carcass until the larvae developed to about a millimetre in length. In other words, if the police investigation was successful, there should not have been any insects of this length on Su Heshan's corpse. If there was an insect of this length on the body, it could only mean two things: that the insect had moved from the carcass of another animal to the body of its victim, and that the crime had been committed not on Bird Island or on the ship, but somewhere else. If it was the first case, then it meant that there were dead animals nearby. However, this situation could be ruled out since Su Heshan's body was found on the ship. According to the police records at the time, there was no mention of other animals being searched on board. The second possibility can also be ruled out because the police searched the entire island and did not mention that a place on the island could have been the scene of the crime. "

"Do you mean to say that Su Heshan's body might have come from a location that has yet to be discovered?"

Shen Yuan nodded his head, "I found some strange symbols in Su Heshan's room. According to those characters, I found a very warm cave at the foot of the mountain on the other side of Bird Island River. There were footprints and marks of heavy objects being dragged inside the cave. If I'm not wrong, Su Heshan might have been killed there. I need to do some laboratory experiments on insects first, and when necessary, I will go out in the field and do some further experiments. "

"Well, it looks like there's something special about this case."

"I was wondering, could this be a very strange case? In any case, I would rather believe in the judgment of science than in the facts before me. Therefore, I want to use my experiments to confirm my thoughts, and I need your help. "

"This case is handled by the City of Lai Public Security. I can't meddle in it casually."

"All I need is for you to go into that cave and see if I'm right."

"What does that mean? Could it be that when I looked around the scene, I felt that the murder scene wasn't on board the ship, so I could prove something? Can you use this to prove what the police of Lai City did wrong? "

"My intuition is that Su Heshan shouldn't have died at that time. Did the Public Security of the City of Lai make a mistake on some investigation segment or hide something?"

"What does that mean? That means your girlfriend is still alive? "