differ,—the earthworms from the bimana, and the cartilaginous _worms_ from the Placoids; and the classification which tags them together, whether it be that of Aristotle or that of Cuvier, cannot be converted into a sort of minus quantity, of force enough to detract from the value and standing of the bimana in the one case, or of the true Placoids in the other. It is in no degree derogatory to the human family that earthworms possess red blood; it is in no degree derogatory to the true Placoids that the _Suctorii_ possess cartilaginous skeletons. Let the reader now mark the use which has been made, by the author of the “Vestiges,” of the name and authority of Linnæus. “Linnæus,” he states, “was so impressed by the low character of many of this order, (the _Chondropterygii_,) that he actually ranked them with worms.” Now, what is the fact here? Simply that Linnæus had no such general order as the _Chondropterygii_ in his eye at all. Though chiefly remarkable as a naturalist for the artificialness of his classifications, his estimate of the cartilaginous fishes was remarkable—though carried too far in its extremes, and in some degree founded in error—for an opposite quality. It was an estimate formed, in the main, on a natural basis. Instead of taking their cartilaginous skeleton into account, he looked chiefly at their standing as animals; and, struck with that extent of front which they present, and with both their superiority on the extreme right, and their inferiority on the extreme left, to the ordinary fishes, he erected them into two separate orders, the one lower and the other higher than the members of the osseous line. And so far was he from regarding the true Placoids—those _Chondropterygii_ which to an internal skeleton of cartilage add external plates, points, or spines of bone—as low in the scale, that he actually raised them above fishes altogether, by erecting them into an order of reptiles,—the older _Amphibia Nantes_. Surely, if the name of Linnæus was to be introduced into this controversy at all, it ought to have been in connection with _this_ special fact; seeing that the point to be determined in the question under discussion is simply the place and standing of that very order which the naturalist rated so high,—not the place and standing of the order which he degraded. It so happens that there is one of the _Chondropterygii_ which, so far from being a true Placoid, does not possess a single osseous plate, point, or spine: it is a worm like creature, without eyes, without movable jaws, without vertebral joints, without scales, always enveloped in slime, and greatly abhorred by our Scotch boatmen of the Moray Frith, who hold that it burrows, like the grave-worm, in the decaying bodies of the dead. And this creature, “the glutinous hag,” or, according to north-country fishermen, the “ramper-eel,” or “poison-ramper,” was regarded by Linnæus as belonging, not to the class of fishes, but to the Vermes. Now, _this_