What is the main point of this article about snails?

Snail this article is mainly about the small snail looking at the heavy and thick shell on his back, while caterpillars and earthworms have no bones but no heavy and thick shells. Mother told the little snail that because the caterpillar will turn into a butterfly, the sky will protect him, the earthworm will get into the soil, and the soil will protect him, but we snails can't turn into butterflies and get into the soil like the caterpillar, so we carry a heavy and thick shell on our backs to protect ourselves.

The literary genre of snails

This is a lyric prose. The author takes "Snail" as the topic and materializes himself as a snail to express his feelings. The article is fluent in language, sincere in feelings, vivid in details, profound in conception, rich in meaning and substantial in content. Stories with moral or obvious educational significance are short in structure and often use metonymy, so that the educational theme or profound truth can be reflected in simple stories.