It is snail (sī) powder.

Snail, sī, Chinese character, basic meaning [螺～] see "snail".

Snail [snail]. A common name for a number of small species of the snail family. The shell is annular, or with spiny or papillate projections on the surface, and is edible.

Snail, snail. --Ming Mei-ying, Zi Hui (字汇)

康熙字典

《唐韵》疏夷切《集韵》霜夷切，音师. The name of the insect, snail.

Expanded Information

The snail often inhabits lakes, ponds, paddy fields, and slow-flowing rivers and streams that are warm in the winter and cool in the summer, and have soft, bait-rich substrates.

It's optimal growing water temperature is around 20~25℃, and the feeding activity stops when the water temperature reaches below 15℃ and above 30℃.

When the temperature is below 10 ℃, it will go into hibernation, and when the water temperature returns to 15 ℃, it will come out of the hole to feed again.

Artificial cultivation of snails can be dug special pool feeding, but also the use of natural rice paddies, swamps, ditches, but also with fish mixed culture. However, it is required that the breeding water is non-toxic, harmless and non-polluting. If the use of paddy farming, you can not apply pesticides, can not be plowed and harrowed, and should be installed into the water outlet wire or plastic mesh, in order to control.

Baidu Encyclopedia-Snail

Baidu Encyclopedia-Snail