On examining a large jelly-fish, it will be noticed to have not only four round bodies on the top, round the centre, and the four lobes hanging down beneath, but that the edges of the body are not quite round, but are notched, so as to make eight lobes to it. And if a little care be taken, marks can be seen on the under part of the body, from the round centre spots to each of the eight splits in the disk; and a magnifying-glass shows a little substance there which feels gritty, and is sometimes colored. Other branching tube-marks pass from the midst of the body to the edge of the umbrella, and a tube runs all round the edge. The tubes communicate in the midst of the body with a cavity, into which the finger can pass between the four under lobes--the stomach--and the digested matters pass into them to nourish the creature. Around the disk or umbrella, and outside the circular tube, is the fringe of hairs which have, to a certain extent, to do with the capture of prey. Each consists of a filmy substance, in which are fixed thread-cells, not very unlike those of the sea-anemone, but they have longer barbs and sharper thorns stretching out from them. Any violence or irritation causes the thread to shoot forth and to injure. The rest of the body of the Medusa is covered with an excessively thin skin, which has movable cilia upon it. It is supposed, and with some reason--for nervous threads and bodies have been found on the disk, close to the gritty bodies especially--that these last are eyes, or ears, or both. The nerves supply the muscles that move the umbrella, and cause it to expand and contract, and the muscles are remarkable, for some are not simple contracting fibres all made of one piece, as in the Anemone tribe. The jelly-fish, when in full vigor and weighing many pounds, must catch and eat much, and the manner in which this is done is by no means perfectly understood. The food is digested, and the results are taken from the stomach into the numerous tubes in the body, where they nourish the tissues. The movements of the animal and its extremely delicate membranes enable much water to come in contact with it, and it breathes by that means, for there are no special gills or lungs.