If this is about H.D.'s poem "Sea Rose", then the answer is the olfactory sense (sense of smell).
In the last stanza, we've got the second contrast in the poem (the first one was "a wet rose single on a stem"): a "spice rose", which is a particular kind of rose, very lavish and beautiful. "Acrid fragrance" is a unique feature of the sea rose that the speaker talks to, and she doubts that this spice rose can have it. In other words, even though the sea rose is "harsh" and "marred", atrophied, destroyed by the sand and the winds, it still has a more distinct and beautiful smell (even though it is acrid) than a regular, nurtured, home-grown rose.