added, in the third Figure of the IX. Scheme, of a piece of it, which you may perceive represents a confus'd heap of the fibrous parts curiously jointed and implicated. The joints are, for the most part, where three fibres onely meet, for I have very seldom met with any that had four.
At these joints there is no one of the three that seems to be the stock whereon the other grow, but each of the fibres are, for the most part, of an equal bigness, and seem each of them to have an equal share in the joint; the fibres are all of them much about the same bigness, not smaller towards the top of the Sponge, and bigger neerer the bottom or root, as is usuall in Plants, the length of each between the joints, is very irregular and different; the distance between some two joints, being ten or twelve times more then between some others.
Nor are the joints regular, and of an equitriagonal Figure, but, for the most part, the three fibres so meet, that they compose three angles very differing all of them from one another.
The meshes likewise, and holes of this reticulated body, are not less various and irregular: some bilateral, others trilateral, and quadrilateral Figures; nay, I have observ'd some meshes to have 5, 6, 7, 8, or 9. sides, and some to have onely one, so exceeding various is the Lusus Naturæ in this body.
As to the outward appearance of this Vegetative body, they are so usuall every where, that I need not describe them, consisting of a soft and porous substance, representing a Lock, sometimes a fleece of Wooll; but it has besides these small microscopical pores which lie between the fibres, a multitude of round pores or holes, which, from the top of it, pierce into the body, and sometimes go quite through to the bottom.
I have observ'd many of these Sponges, to have included likewise in the midst of their fibrous contextures, pretty large friable stones, which must either have been inclos'd whil'st this Vegetable was in formation, or generated in those places after it was perfectly shap'd. The later of which seems the more improbable, because I did not find that any of these stony substances were perforated with the fibres of the Sponge.
I have never seen nor been enform'd of the true manner of the growing of Sponges on the Rock; whether they are found to increase from little to great, like Vegetables, that is, part after part, or like Animals, all parts equally growing together; or whether they be matrices or feed-baggs of any kind of Fishes, or some kind of watry Insect; or whether they are at any times more soft and tender, or of another nature and texture, which things, if I knew how[errata 1], I should much desire to be informed of: but from a cursory view that I at first made with my Microscope, and some other trials, I supposed it to be some Animal substance cast out, and fastned upon the Rocks in the form of a froth, or congeries of bubbles, like that which I have often observ'd on Rosemary, and other Plants (wherein is included a little Insect) that all the little films which divide these bubbles one from another, did presently, almost after the substance began to grow a little harder, break, and leave onely the thread behind, which might be, as 'twere, the angle or thread between the bubbles, that the
Errata
