11. Proteus Diffluens.
P. in ramulos diffluens, [Plate XXV.] Fig. 2 and 3. Proteus, branching itself out in a variety of directions.
A very singular animalculum, appearing only as a grey mucous mass; it is filled with a number of black globules of different sizes, and is continually changing its figure. Being formed of a gelatinous pellucid substance, the shape is easily altered, and it pushes out branches of different lengths and breadths. The globules which are within divide and pass immediately into the new formed parts, always following the various changes of form in the animalcula. The changes that are observed in the form of this little creature, do not arise from any extraneous cause, but are entirely dependent on its internal powers. It is to be met with but very seldom; the indefatigable Müller only saw it twice, although he examined such an immense variety of infusions. It is to be found in fenny situations.
12. Proteus Tenax.
P. in spiculum diffluens, [Plate XXV.] Fig. 4 and 5. Proteus, running out into a fine point.
A gelatinous pellucid body, stored with black molecules; it changes its form like the preceding, but always in a regular order, first extending itself out in a straight line, Fig. 5, the lower part terminating in an acute bright point, a, without any intestines; and the globules being all collected in the upper part, c, it next draws the pointed end up towards the middle of the body, swelling it into a round form. The contraction goes on for some time, after which the lower part is swelled out as it is represented in Fig. 4, d; the point a, is afterwards projected from this ventricose part. It passes through five different forms before it arrives at that which is seen, at Fig. 4. It scarcely moves from one spot, only bending about sideways. It is to be found in river water.
III. VOLVOX.
Volvox inconspicuus, simplicissimus, pellucidus, sphæricus. An invisible, very simple, pellucid, spherical worm.
13. Volvox Punctum.
V. sphæricus, nigricans, puncto lucido. Spherical, of a black colour, with a lucid point.