H. macrohista, along with H. bonnellii, are the only members of the genus with a very large inner web. H. macrohista is apparently much the smaller of the two with all known individuals less than 70 mm ML while H. bonnellii is known from individuals as large as about 330 mm ML. The function of the deep web is unknown. However, its heavy pigmentation would make it an effective tool in concealing the bioluminescence emitted by struggling prey. A prudent predator, in this dark habitat, does not want to attract the attention of larger animals. If true, one wonders why all histioteuthis haven't adopted this strategy.