THE AMCEB.E OF MAN 



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gena nucleus of E. histolytica, a distinction from the central karyosome of E. coll 

 which has only a very narrow clear zone surrounding it. 



At the present we differentiate between two types of nucleus the 

 histolytica one, which is found in acute attacks of dysentery and 







FIG. 59. Important pathogenic protozoa of the' intestinal tract. (la) Motile E, 

 coli. Note large amount and peripheral arrangement of chromatin in nucleus. ( ib ) 

 Encysted E. coli. Note larger size than E. histolytica cyst, 8 ring form nuclei and 

 absence of chromidial bodies. (2) Motile E. histolytica from acute dysenteric stool. 

 Note histolytica nucleus with scanty chromatin. (3) Tetragena type of E. histo- 

 lytica from case of chronic dysentery. Note greater amount of chromatin and central 

 karyosome with centriole. (4a) Preencysted E. histolytica from carrier. Note small 

 size and heavy peripheral ring of chromatin in nucleus making this feature of chrom- 

 atin in nucleus similar to the larger E. coli. (4_b) Encysted E. histolytica from 

 dysentery convalescent. Note small size, 4 ring nuclei and a dark chromatin stain- 

 ing mass, "chromidial body." (sa and 5b) Motile and encysted cultural amoebae 

 from Manila water supply. (6a and 6b) Oocyst and sporozoite production in 4 

 spores of Eimeria stiedae. (ya and 76) Oocyst with 2 sporoblasts and oocyst with 

 2 spores containing 4 sporozoites of Isopora bigemina. (8a and 8b) Vegetative and 

 encysted Trichomonas intestinalis . (pa and pb) Vegetative and encysted Lamblia 

 intestinalis. (10) Balantidium coli. Illustrations of amoebae from Walker others 

 from Doflein. 



shows a delicate nuclear membrane with scattered chromatin granules 

 in its inner side and as a rule a very small central karyosome. The 

 tetragena type has a much thicker nuclear membrane and is the one 

 generally found in pathogenic amoebae in chronic dysentery. Of 



