. A manual of zoology. Zoology. 202 PROTOZOA. Reproduction is nearly always by fission. In many species conjugation is known, best in those plant-like forms, the Volvo- cina, where two individuals fuse completely to a resting spore. In the colonial Volvocina the conjugating individuals are unequal in size, some animals of the colony growing to large immobile oospheres, while others by continued division form groups of minute active zoospores or spermatozoids. When fertilized by the zoospore the oospheres fall to the ground, become encysted, become brown in color, and enter a resting stage befo
. A manual of zoology. Zoology. 202 PROTOZOA. Reproduction is nearly always by fission. In many species conjugation is known, best in those plant-like forms, the Volvo- cina, where two individuals fuse completely to a resting spore. In the colonial Volvocina the conjugating individuals are unequal in size, some animals of the colony growing to large immobile oospheres, while others by continued division form groups of minute active zoospores or spermatozoids. When fertilized by the zoospore the oospheres fall to the ground, become encysted, become brown in color, and enter a resting stage before they form a new colony by division. Sub Order I. PHYTOFLAGELLATA. Plant-like chlorophyl-bearhig flagellates, mostly with eye-specks. Volvocina : Volvox glohator,* green sphere mm. in diameter, consisting of thousands of individuals which propel the colony by their flagella. Euglenidge : Euglena viridis * (fig. 134), solitary, coloring small pools bright green (a red variety colors them purple) by their immense numbers. Chrysomonadina, plant-like in nourishment but rarely taking solid food : Dinohryon * (fig. 136). Sub Order II. CHOANOFLAGELLATA. With collars ; mostly small colonial forms. Codoslga * (tig. 138, B) ; Conodadxum, numerous indi- viduals united on a stalk (fig. 130). Sub Order III. EUFLAGELLATA. Animal flagellates, taking solid particles of food either by pseudopodia or by a more or less developed cytostome. Monadina. Here belong, besides numerous free forms, several parasites of man : Lamhlia iCercomonas) intestinalis, fig. 139 {Mega-. FiG. 139. Fig. UO. Fig. Vi^.—Lamhlia intesthuilis. (After Grassi.) Front and side views, i/. nucleus Fig. liO.—Trichomonas vaginalis. (After Blochmann.) », nucleus (fourth flageUuni lacking in figure). stoma erUericum); also in rats and mice : Trichoino7ias hominis (T. infes- tiitalis), both in small intestine. T. vaginalis (fig. 140).. Please note that these images are extracted from scanned page images that may have
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