How does the variation of goldfish eyes change?

There are four main types of goldfish eyes: normal eyes, dzi-bead eyes, sky-watching eyes and blister eyes. The normal eyes are the same as those of wild crucian carp, and the other three are all mutated eyes. The eyes of dzi beads are enlarged, obviously protruding from the orbit and facing the sides of the body; Seeing the eye of the celestial sphere is very similar to the eye of the dzi bead, and the eyeball also protrudes from the orbit. The difference is that the pupil of the celestial eye turns 90 degrees upward and faces the sky; Bubble eyes are not convex, but there is a big translucent bubble under each eye, like two small lanterns. When goldfish swim slowly, bubbles will vibrate from side to side (bubbles are too small to vibrate), which is very attractive.