Fig. 11. Two portions of the stem of a sea-weed. a.-The summit of a growing shoot. Vegetable organisms grew upon every part of the outer layer of the formed material, but these are only represented in the upper part of the drawing. The external membrane is increased in thickness by the deposition of new layers from the germinal matter. The continuity between the masses of germinal matter is still seen, and the manner in which buds are formed, is represented. b.-From an older part of the stem, showing the mode of formation of the

spores.

Fig. 12. A thin section of a very rapidly growing fungus of very simple structure. At a are seen portions of the simple membranous walls of large spaces, in which the masses of germinal matter were situated. b.-Some of the smallest masses of germinal matter, entire, and separated into their component spherules, magnified 1,700 diameters. It was not possible to demonstrate the formed material, in many specimens. C.Larger masses of germinal matter magnified 700 diameters.

These figures illustrate the following points :

1. That every elementary part of an organism, consists of matter in two states. Germinal matter, growing, active, undergoing change. Formed material, which has been formed from the germinal matter, passive, and not capable of growing or of selecting nutrient substances.

2. That the formed material is on the outside of the germinal matter, and is increased in thickness by the deposition of new matter on its inner surface. The outer part of the formed material is the oldest; the inner that which has only just passed from the state of germinal matter.

3. That the masses of germinal matter are composed of smaller spherical particles, and these, again, of smaller spherules. (Fig. 10 b, fig. 12 b.)

PLATE III.

To illustrate the supposed structure of an elementary part, the structure of the cells' of the potato, and the formation of the starch granules.

Fig. 13. Spherical particles of germinal matter composed of smaller spherules. The smallest spherules are only represented in one or two instances. The quiescent portion of the germinal matter (nucleus) is indicated by the dark colour of the spherules.

Fig. 14. Supposed structure of one of the smallest component spherules of Fig. 5, very highly magnified.

Fig. 15. Germinal matter and formed material of a structure like the liver cell. At the outer part the formed material is gradually being resolved into biliary, and other constituents.

Fig. 16. Germinal matter and formed material of ordinary tendon.

Fig. 17. Diagram to show the manner in which fatty matter and other substances resulting from changes occurring in the germinal matter, accumulate in its central part. The germinal matter at last forms a very thin layer between these particles and the formed material of which the investing membrane or cell wall is composed.

Fig. 18. Diagram to show the manner in which the pores in certain vegetable cells, and the canaliculi of bone are left during the deposition of hard matter in the formed material from without inwards.

Fig. 19. A fully formed starch-holding cell of the common potato. The primordial utricle has been removed from the lower half, in order to show the starch globules within, more distinctly. The nucleus and nucleolus are seen in the remaining portion. Around are portions of neighbouring cells, the walls of which are separated here and there by compressed bubbles of air indicated by the very dark shading. On the