So small are these creatures that the largest specimen will be found to be smaller than the smallest pin’s head. Examine how we will, there will be found no mouth, no stomach, no muscles, no nerves, no parts of any kind. The animal looks merely like a minute drop of gum with fine grains diffused throughout, floating in the water, some times with outstretched arms, and at other times as a simple drop. An analysis of the matter of which it is composed shows it to be much the same as a speck of white-of-egg. Yet it is alive, for it breathes. Kept in a drop of water, it uses up the oxygen it contains, and renders the water foul by the carbonic acid it breathes out. The arms, so necessary in the procurement of food, can be drawn in and thrown out when and where the animal chooses, showing that some option is undoubtedly exercised in the matter. Minute jelly-plants, that live in the water, and even higher animals than itself, constitute its food. The presence of an animal with a shell does not deter it from attack, for it is just as able to deal with it as with the softer, shell-less kinds, sucking their jelly-like contents, and discarding the empty, innutritious shells. Quite as interesting among the Moners, to which the Finger Slime belongs, is the _Protomyxa aurantiaca_, a shapeless bit of transparent matter, containing merely circulating granules. Locomotion is effected by extending the body into pseudopodia, or false feet, and contracting them. Its movement is slow and gliding. When at rest it appears as a mere lump of jelly, but its whole demeanor changes when in the presence of a living animal suited for food. Fine threads immediately begin to shoot out from all sides, which fuse about the unsuspecting prey, while all the little grains in the slime course to and fro. For five or six hours the little fellow hugs closely round the prey until it has become thoroughly absorbed, at least the nutritious parts, into its body-mass, when it draws itself away, or back into its original place, leaving by its side the skeleton of its late victim. Without eyes or ears or parts of any kind it knows how to find its food; without muscles or limbs it is able to seize it; without a mouth it can suck out its living body, and without a stomach it can digest the food in the midst of its own slime, and cast out the parts for which it has no use. [Illustration: PROTOMYXA FEEDING.] When Protomyxa has become a burden to itself it divides itself by a simple process of fission, each part being complete in itself, or it assumes a thick covering, becoming encysted, as it is termed. In a little while the enclosed mass divides into spheres, the cell-wall bursts, and the little spheres, which have now taken on a sort of tadpole shape, float out upon the water, where they soon assume the parent-form.