ILLUSTRATIONS 



FIG. PAGE 



1. Sagittal section of head to show spread of suppuration from infected 



teeth; and also location of retropharyngeal abscesses _ _ _ _ 73 



2. Portals of infection and the most frequent nodes involved in tubercu- 



losis of the cervical lymph nodes __________ 75 



3. Pulmonary pleural, and tracheal lymphatic drainage _____ 76 



4. Drainage of periphery of lung ____________ 76 



5. The supposed intergenetic relationships and convertibility of cells of 



the "macrophage (reticulo-endothelial) system" of mammals _ 92 



6. Distribution of agglutinins and agglutinogens in human blood groups 171 



7. Graph showing distribution of agglutinogens in apes resembling those 



in man ______________---175 



8. Pseudoagglutination or rouleaux formation of red cells _ _ _ _ 185 



9. True agglutination of red cells ____-______-185 



10. Bed cell before adding immune serum containing hemagglutinin 



(Color) ______-____-__--- 214 



11. Red cell after adding hemagglutinin partly or completely filmed with 



antibody globulin absorbed from immune serum (Color) _ _ _ 214 



12. Measurement of cohesive force of bacteria ________ 216 



13. Interfacial tension technique of Mudd _________ 21 7 



14. Durham's conception of the multiplicity of cellular antigens _ _ _ 319 



15. Positive Widal test _______________ 380 



16. Negative Widal test ________-__-_-- 381 



17. Graph showing fluctuation in agglutinins in partially immune and im- 



mune animals during infection with P. tularensis _ _ _ _ 388 

 IS. Type II pneumococeus in sputum mixed with Type I antiserum (rab- 

 bit) ; no "quellung" _____________ 397 



19. Type II pneumococeus in sputum mixed with Type II antiserum (rab- 



bit) ; "quellung" reaction ___________ 397 



20. Photomicrograph of a strongly positive Kline test ______ 459 



21. Photomicrograph of a moderately positive Kline test _____ 459 



22. Photomicrograph of a weakly positive Kline test ______ 459 



23. Photomicrograph of a negative Kline test ________ 459 



24. Negatively charged particle surrounded by single layer of positive 



charges, theory of Helmholtz _________--587 



25. Negatively charged particle surrounded by diffuse atmospliere of posi- 



tively charged particles, theory suggested by Gouy _ _ _ _ 587 



26. Orientation of molecules of an alcohol (or an organic acid) at the 



surface of its aqueous solution __________ 590 



27. Factors involved in dispersion and precipitation of colloids _ _ _ 592 



24 



