T. Goodey and a. W. Weldings 
559 
Fig. 3. E. gingivalis forms showing bacteria ingested as the source of food. Stained. 
Iron-haematoxj’lin. 
Fig. 4. E. gingivalis, trophic form showing characteristic round bodies within food 
vacuoles, and rods of bacteria at posterior end. Iron-haematoxylin. 
Fig. 5. E. gingivalis, very small form 7-5^ long, from pyorrhoea material from child of 
5 j'ears. Iron-haematoxylin. 
Fig. 6. E. gingivalis, bi-nucleate form with the nuclei in focus, the cytoplasm is out of 
focus. Iron-haematoxylin. 
Fig. 7. E. gingivalis, late stage of fission, the connecting strand of protoplasm is slightly 
out of focus.. Iron-haematoxylin. 
Fig. 8. Endothelial cell with an ingested polymorphonuclear leucocyte towards lower 
end slightly overlapping the cell nucleus. Iron-haematoxylin. From pyorrhoea pus. 
Fig. 9. Polymorphonuclear leucocyte from gum, ingesting a rod of bacteria and showing 
the open character of the lobed nucleus. Fixed absolute alcohol, stained methyl- 
green. 
Fig. 9 a. Polymorphonuclear salivary corpuscle showing the rounded almost homo¬ 
geneous lobes of the nucleus. Stained iron-haematoxyUn. 
PLATE XXI. 
Camera lucida drawings, all magnified 2725 diameters. All stained with iron- 
haematoxyhn. 
Figs. 10, 11,. 12, 13, drawings of E. gingivalis showing characteristic inclusions of various 
shapes and sizes and staining reaction. Fig. 13 shows the cytoplasm of the amoeba 
in an alveolate condition, whilst the inclusions show small pieces of cytoplasm attached 
to the chromatinic material. Fig. 13 a, b and c, deeply stained nuclear lobes with 
attached cytoplasmic fragments from same film as Fig. 13. 
Fig 14 a-m, disiritegrating salivary corpuscles and their products, showing the same 
characteristic appearances as the amoeba inclusions, drawn from salivary and 
tonsillar smears and from pyorrhoea pus and food debris smears. 
Fig. 15. Entamoeba coli, a small trophic form showing two ingested yeasts lying in one 
vacuole, note the different appearance of these from the inclusions in E. gingivalis. 
Fig. 16. Outline of red blood corpuscle drawn to the same scale of magnification for 
purposes of comparison. 
PLATE XXII. 
Tetratrichonionas buccalis n. sp. Camera lucida drawings magnified 4100 diameters. 
All stained with iron-haematoxylin. 
Figs. 17-20. Four different free swimming trophic forms showing the four anterior 
flagella, the undulating membrane and the relations of nucleus, blepharoplast and 
rhizoplast, and also the axostyle. In Fig. 19, the chromatinic basal rod connected 
with the undulating membrane appears to be absent. 
Fig. 21. An organism in a much extended amoeboid condition showing numerous ingested 
bacteria and the axostyle as a long narrow rod. The outline of the nucleus is lost, 
owing to the differentiation having been carried rather too far. 
