English: Flagellata:

1. Chlamydomonas pulvisculus, Ehr. (Chlamydomonadidae) free-swimming individual.

   a = nucleus.
   b = contractile vacuole.
   c = starch corpuscle.
   d = cellulose investment.
   e = stigma (eye-spot).

2. Resting stage of the same, with fourfold division of the cell-contents. Letters as before.

3. Breaking up of the cell-contents into minute biflagellate swarm-spores, which escape, and whose history is not further known.

4. Syncrypta volvox, Ehr. (Chrysomonadidae). A colony enclosed by a common gelatinous test c.

   a = stigma.
   b = vacuole (non-contractile).

5. Uroglena volvox, Ehr. (Chrysomonadidae). Half of a large colony, the flagellates embedded in a common jelly.

6. Chlorogonium euchlorum, Ehr. (Chlamydomonadidae).

   a = nucleus.
   b = contractile vacuole.
   c = starch grain.
   d = eye-spot.

7. Chlorogonium euchlorum, Ehr. (Chlamydomonadidae). Copulation of two liberated microgonidia.

   a = nucleus.
   b = contractile vacuole.
   d = eye-spot (so-called).

8. Colony of Dinobryon sertularia, Ehr. (Chrysomonadidae).

9. Haematococcus palustris, Girod (= Chlamydococcus, Braun, Protococcus, Cohn), one of the Chrysomonadidae; ordinary individual with widely separated test.

   a = nucleus.
   b = contractile vacuole.
   c = amylon nucleus (pyrenoid).

10. Dividing resting stage of the same, with eight fission products in the common test e.

11. A microgonidium of the same.

12. Phalansterium consociatum, Cienk. (Choanoflagellata); × 325. Disk-like colony.

13. Euglena viridis, Ehr.; × 300 (Euglenidae).

   a = pigment spot (stigma).
   b = clear space.
   c = paramylum granules.
   d = chromatophor (endochrome plate).

14. Gonium pectorale, O. F. Müller (Volvocineae). Colony seen from the flat side; × 300.

   a = nucleus.
   b = contractile vacuole.
   c = amylon nucleus.

15. Dinobryon sertularia, Ehr. (Chrysomonadidae).

   a = nucleus.
   b = contractile vacuole.
   c = amylon nucleus.
   d = free colourless flagellates, probably not belonging to Dinobryon.
   e = stigma (eye-spot).
   f = chromatophors.

16. Peranema trichophorum, Ehr. (Peranemidae), creeping individual seen from the back; × 140.

   c = pharynx.
   d = mouth.

17. Anterior end of Euglena acus, Ehr., in profile.

   a = mouth.
   b = vacuoles.
   c = pharynx.
   d = stigma (eye-spot).
   e = paramylum-body.
   f = chlorophyll corpuscles.

18. Part of the surface of a colony of Volvox globator, L. (Volvocidae), showing the intercellular connective fibrils.

   a = nucleus.
   b = contractile vacuole.
   c = starch granule.

19. Two microgametes (spermatozoa) of Volvox globator, L.

   a = nucleus.
   b = contractile vacuole.

20. Ripe asexually produced daughter-individual of Volvox minor, Stein, still enclosed in the cyst of the partheno-gonidium.

   a = young, partheno-gonidia.

21. 22. Trypanosoma sanguinis, Gruby (Haematoflagellates), from the blood of Rana esculenta.

   a = nucleus; × 500.

23-26. Reproduction of Bodo caudatus, Duj. (Bodonidae), after Dallinger and Drysdale:—23, fusion of several individuals (plasmodium); 24, encysted fusion-product dividing into four; 25, later into eight; 26, cyst filled with swarm-spores.

27. Distigma proteus, Ehbg., O.F. Müller (Euglenidae); × 440. Individual with the two flagella, and strongly contracting hinder region of the body.

28. The same devoid of flagella.

   c, c = the two dark pigment spots (so-called eyes) near the mouth.

29. Oicomonas termo (Monas termo) Ehr. (one of the Oicomonadidae).

   c = food-ingesting vacuole.
   d = food-particle; × 440.

30. The food-particle d has now been ingested by the vacuole.

31. Oicomonas mutabilis, Kent (Oicomonadidae), with adherent stalk.

   a = nucleus.
   b = contractile vacuole.
   c = food-particle in food vacuole.

32, 33. Cercomonas crassicauda, Duj. (Oicomonadidae), showing two conditions of the pseudo-podium-protruding tail.

   a = nucleus.
   b = contractile vacuoles.

c = mouth.