Amebas with so-called limax-shaped bodies do not possess surface layers that carry particles forward with the same speed as those amebas with broad bodies. It is only occasionally that large amebas such as _proteus_ are found in a limax or clavate shape. One of the most favorable of the large amebas in this respect is _discoides_. It is frequently found in clavate shape and it possesses the further advantage in being nearly cylindrical in cross section. It is also more in the habit of loping along the surface in the manner described by Dellinger (’06, p. 57) so that what is observed to take place in _discoides_ in the clavate shape, holds likewise for free pseudopods extended into the water out of contact with a solid support (Figure 22). [Illustration: Figure 21. Illustrating the similarity of the movement of the surface layer of _Amoeba verrucosa_ with that of _A. sphaeronucleosus_. A group of three particles, connected by dotted lines for reference, change their relative positions as the ameba (_verrucosa_) changes its direction of movement. Length of the ameba, 150 microns.] [Illustration: Figure 22. Illustrating the movements of an _Amoeba proteus_, after Dellinger. At _c_ in stage 2 a pseudopod is projected which fastens itself to the substratum as shown at _c_, 3, while _a_, 2, is pulled loose. In 4 another pseudopod is projected which fastens itself at _d_. The ameba is not in contact with the substratum at all points on its under side.] In figure 23 is shown a clavate _discoides_ with a small particle attached to its side. The particle moved forward until it came to lie at the anterior edge, 10. The speed of the particle from 1 to 10 was 1.36 times as fast as that of the ameba, a much slower rate than was observed in _sphaeronucleosus_. At 6 a new pseudopod was projected for a short distance, thus increasing the amount of new ectoplasm forming in proportion to that of the whole ameba. This change was reflected in the increased speed of the particle, which moved 1.64 times as fast as the ameba from 5 to 6. At 10 the anterior end again spread out and again the particle moved faster--twice as fast as the ameba from 9 to 10. Stages 11, 12, 13 are added to show that the particles do not tend to go to the under surface but remain at or very near the tip. The slight irregularity of the waves of hyaloplasm pushed out at the anterior end accounts for the changing position of the particle after it has reached the anterior edge. The particle remained at the edge of the advancing ameba for several minutes after the stage drawn at 13. [Illustration: Figure 23. Showing the movement of a particle on the surface layer of an _Amoeba discoides_. The particle remained on the anterior end of the ameba for several minutes after stage 13. The ameba was about 320 microns long.]