For myself, therefore, I doubt the reason given for his choosing the latter position, and I should doubt the fact of his doing so, if there were not some evidence for it. For the remora often attaches itself to the hull of a ship, and it is natural to suppose that, in such cases, it mistakes the ship for a large shark, or a whale. Now when it does so, it either sticks to, or swims near, the fore part of the vessel, but not behind, or astern. Thus, Professor Moseley describes it as “swimming for weeks, near the water-surface, just a foot in front of the cut-water,” and he remarks on this that “if it swam just behind the stern, it would get plenty of food, whereas in front of the bow it gets nothing whatever.” “Nevertheless,” continues the professor, “it stays on at what, in a shark, is, of course, the right place, ready to be at the beast’s mouth directly food is found.” This, therefore, seems to establish the fact. As to the reason of it, it has just occurred to me that when a shark bites a piece out of the living body of any creature, there must be a great rush of blood, and the remora would get the best benefit of this, if it was just by the shark’s mouth, at the time. Or, again, the little fish may feel more secure there than elsewhere. A shark is a large thing—twenty, thirty, or forty feet long sometimes—and many voracious fish that might prefer to keep away from its head, might be bold enough, perhaps, to approach its tail or the after part of its body. The remora, apparently, is not in the habit of going inside the shark’s mouth, as does the pilot-fish—so it may think the next safest thing to that is to keep as near it as it can, on the outside.