OCTOMITUS HOMINIS 



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Genus i. Octomitus Prowazek, 1904. 



Definition. — Octomitidae, parasitic with anteriorly three pairs 

 and posteriorly one pair of flagella ; nucleus single, bilaterally lobed 

 or doubled; sucker absent. 



Type Species. — 0. intestinalis Prowazek, 1904, found in rats. 



Classification. — The known species of Octomitus may be recog- 

 nized as follows : — 



A. Nucleus situate close to the anterior end:— 



I. Nucleus often hilohed— Dujar dim. 

 II. Nucleus double: — 



(a) Measurements 8-12 x 5-7 microns — Intestinalis, 



(b) Measurements 4-6 x 2 microns— M^^ns. 



B. Nucleus not situate close to the anterior end:— 



Nucleus single and rounded; size 6x3 microns — Hominis. 



Fig. 143. — Octomiius hominis Chal- Fig. i^^.—OcfomiiMS hominis Chal- 

 mers AND PeKKOLA, I916. MERS AND P E K K O L A, I 9 I 6. 



(X2„ooo.) (X 2,000.) 



Octomitus hominis Chalmers and Pekkola, 1916. 



Definition. — Octomitus with single rounded nucleus, not situate 

 close to anterior end. 



Morphology. — Small fusiform or pear-shaped flagellates, in size 

 5-6-6-0 X 2-8-3-0 microns. 



When examined in the stained condition it showed a circular 

 clearly defined nucleus (Figs. 143 and 144), measuring about 

 1-4 microns in transverse diameter, and lying near the junction of 

 the anterior third with the posterior two-thirds of the body. This 

 nucleus is bounded by a well-marked membrane, which limits the 

 homogeneous dark staining contents, in which there is often a 

 centrally or excentrically placed karyosome. 



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