I continue to agree that the figure on the box is a fish. And now with this inscription and photos of it, I find the evidence convincing that the artist was depicting Jonah. Further, given that this pictorial is on a bone box from first-century Jerusalem, it is plausible that the reference is to resurrection.
With this find, we have some type of Jew in the first century for whom the Jonah story made sense within the context of death. So I am moving in the direction that we may be seeing here evidence of an early Christian-Jewish tomb.