Definition of "enigmatical"

He saw now clearly that the sole crew of the vessel was these two dead men, and though he could not see their faces, he saw by their outstretched hands, which were all of ragged flesh, that they had been subjected to some strange exceptional process of decay. For a moment his attention concentrated on those two enigmatical bundles of dirty clothes and laxly flung limbs, […]

1905, H. G. Wells, The Empire of the Ants