Nature vs. the Snail

In the "Virginia Wolf" I was vey confused by the beginning but as I began to read I became aware of how often the theme of nature kept reappearing. For instance, "I understand Nature's game-her prompting to take actions as a way of ending any thought that threatens to excite or to pain". (1101) While at the beginning of the text it began with the theme of life and the overall meaning of this mark on the wall, the author took a turn to focus on how nature plays a role in life as well. "Nature counsels, comforts you, instead of enraging you; and if you can't be comforted if you must shatter this hour of peace, think of the mark on the wall." (1101) In this particular passage the author connects the mark on the world with nature, as it comforts it as nature does. The mark on the wall represents comfort, and peace by it's mystery and ability to transform into anything just like nature. However "the mark on the wall was a snail" (1102), so why with all that hype on nature and the talk of the trees, and the woods why would it be a snail? How does the snail represent nature in any sense?