Somewhat more advanced, but still of great simplicity, is the _Protomyxa aurantiaca_ (Pl. 5, Fig. 8), discovered by Haeckel[76] on dead shells of _Spirula_, where it appears as a minute orange speck, which shows well against the clear white of the _Spirula_. Examined with a microscope, the speck is seen to be a spherical mass of orange-coloured, homogeneous, albuminous matter, surrounded by a delicate, structureless membrane. It is obvious from this description that these bodies closely resemble eggs, for which indeed Haeckel at first mistook them. Gradually, however, the yellow sphere broke itself up into smaller spherules (Pl. 5, Fig. 9), after which the containing membrane burst, and the separate spherules, losing their globular form, crept out as small _Amœbæ_ (Pl. 5, Fig. 6), or amœboid bodies. These little bodies moved about, assimilated the minute particles of organic matter, with which they came in contact, and gradually increased in size (Pl. 5, Fig. 7) with more or less rapidity according to the amount of nourishment they were able to obtain. They threw out arms in various directions, and if divided each section maintained its individual existence. After a while their movements ceased, they contracted into a ball, and again secreted round themselves a clear structureless envelope. This completes their life history as observed by Haeckel, who found it easy to retain them in his glasses in perfect health, and who watched them closely. As another illustration I may take the _Magosphæra planula_, discovered by Haeckel on the coast of Norway. In one stage of its existence (Pl. 5, Fig. 10) it is a minute mass of gelatinous matter, which continually alters its form, moves about, feeds, and in fact behaves altogether like the _Amœba_ just described. It does not, however, remain always in this condition. After a while it contracts into a spherical form (Pl. 5, Fig. ii), and secretes round itself a structureless envelope, which, with the nucleus, gives it a very close resemblance to a minute egg.