3237. The nervous system in like manner accompanies the tegument. It consists of two gangliated cords passing along the ventral surface.
3238. As the maxillæ are only repeated feet, so they are rarely wanting, and are, like the latter, disposed after the fashion of scissor-blades. The same holds good of the antennæ; they are mostly in pairs, and consist of a series of rings projecting from the head.
3239. The eyes are usually present, but only as tegumental organs, or placed upon the points of the antennæ.
Class 7. Reticular or Papillary Animals.
3240. The repetition of the Intestinal or Vascular animal, taking place under the dominion of the respiratory system, must be accompanied by the vascular system. The tegument is a vascular, a branchial membrane, a branchial network or skin.
3241. A body with predominating tegumental and intestinal system, is cylindrical. It can only become gross or lump-shaped, if the glandular viscera, such as liver, ovarium and testes, get the upper hand or prevail.
3242. A tegument which appears as a branchial membrane, is annulate or ringed.
3243. An animal, having an annulate respiratory membrane without annulated feet, is a Worm.
Upon the lowest stage the vascular system is still similar to that of the Vascular animals; its blood is a colourless fluid—White Worms, Entozoa.
In order to be a Worm, it is sufficient to have an annulate tegument. Even if the intestine be wanting and the tegument supplies its place; the character is nevertheless complete. Here it is the skin, which digests, while in the Intestinal animals it is the intestine, which digests and breathes. Since it is here the tegument, which undertakes the offices of the whole body; the vessels, liver, and salivary glands are wanting unto the intestine.