Both its motion and rest is very strange, and pleasant, and differing from those of most other creatures I have observ’d; for, where it ceases from moving its body, the tail of it seeming much lighter then the rest of its body, and a little lighter then the water it swims in, presently boys it up to the top of the water, where it hangs suspended with the head always downward; and like our _Antipodes_, if they do by a frisk get below that superficies, they presently ascend again unto it, if they cease moving, until they tread, as it were, under that superficies with their tails; the hanging of these in this posture, put me in mind of a certain creature I have seen in _London_, that was brought out of _America_, which would very firmly suspend it self by the tail, with the head downwards, and was said to keep in that posture, with her young ones in her false belly, which is a Purse, provided by Nature for the production, nutrition, and preservation of her young ones, which is described by _Piso_ in the 24. Chapter of the fifth Book of his Natural History of _Brasil_. The motion of it was with the tail forwards, drawing its self backwards, by the striking to and fro of that tuft which grew out of one of the stumps of its tail. It had another motion, which was more sutable to that of other creatures, and that is, with the head forward; for by the moving of his chaps (if I may so call the parts of his mouth) it was able to move it self downwards very gently towards the bottom, and did, as ’twere, eat up its way through the water. But that which was most observable in this creature, was, its Metamorphosis or change; for having kept several of these Animals in a Glass of Rain-water, in which they were produc’d, I found, after about a fortnight or three weeks keeping, that several of them flew away in Gnats, leaving their husks behind them in the water floating under the surface, the place where these Animals were wont to reside, whil’st they were inhabitants of the water: this made me more diligently to watch them, to see if I could find them at the time of their transformation; and not long after, I observ’d several of them to be changed into an unusual shape, wholly differing from that they were of before, their head and body being grown much bigger and deeper, but not broader, and their belly, or hinder part smaller, and coyl’d, about this great body much of the fashion represented by the prick’d line in the second _Figure_ of the 27. _Scheme_, the head and horns now swam uppermost, and the whole bulk of the body seem’d to be grown much lighter; for when by my frighting of it, it would by frisking out of its tail (in the manner express’d in the Figure by BC) sink it self below the surface towards the bottom; the body would more swiftly re-ascend, then when it was in its former shape.