1 _Amœba coli._ (After Loesch) 29 2 Encysted intestinal amœbæ. (After Grassi) 31 3 _Entamœba coli_, life-cycle. (After Castellani and Chalmers) 32 4 _Entamœba coli_, so-called autogamy. (From Minchin) 34 5 _Entamœba histolytica_ (_tetragena_ form). (After Hartmann) 35 6 _Entamœba histolytica_, ingestion of red blood corpuscles. (After Hartmann) 35 7 _Entamœba histolytica_, section through infected intestinal ulcer. (After Harris) 36 8 _Entamœba histolytica_ (_tetragena_), trophozoite and nuclei. (After Hartmann) 38 9 _Entamœba histolytica_ (_tetragena_), cysts. (After Hartmann) 39 10 _Entamœba buccalis._ (After Leyden and Löwenthal) 43 11 _Entamœba kartulisi._ (After Kartulis) 44 12 _Amœba miurai._ (After Ijima) 46 13 _Chlamydophrys enchelys._ (After Cienkowski) 48 14 _Chlamydophrys enchelys_, encysted. (After Cienkowski) 49 15 _Leydenia gemmipara_, Schaudinn 50 16 _Trichomonas vaginalis._ (After Künstler) 53 17 _Trichomonas intestinalis._ (After Grassi) 54 18 _Trichomonas intestinalis._ (Original, Fantham) 55 19 _Lamblia intestinalis._ (After Wenyon, from Minchin) 58 20 _Lamblia intestinalis._ (After Grassi and Schewiakoff) 59 21 _Cercomonas hominis._ (After Davaine) 61 22 _Cercomonas hominis_, from an echinococcus cyst. (After Lambl) 61 23 _Monas pyophila._ (After Grimm) 62 24 _Prowazekia urinaria._ (After Sinton) 64 25 _Prowazekia urinaria_, excystation. (After Sinton) 65 26 _Trypanosoma brucei_ in division. (After Laveran and Mesnil) 70 27 _Trypanosoma lewisi_, rosettes. (After Laveran and Mesnil) 71 28 _Trypanosoma gambiense._ (After Dutton) 73 29 _Trypanosoma gambiense_, development in vertebrate host. (Original, Fantham) 73 30 _Trypanosoma gambiense_, development in _Glossina palpalis_. (After Robertson) 75 31 _Trypanosoma rhodesiense._ (After Stephens and Fantham) 77 32 Chart showing daily counts of number of Trypanosomes per cubic millimetre of peripheral blood from a case of Rhodesian sleeping sickness. (After Ross and Thomson) 79 33 _Trypanosoma cruzi_, schizogony. (After Chagas, from Castellani and Chalmers) 84