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BIOLOGY: GENERAL AND MEDICAL 



FIG. 25. Diagram of a sagittal section 

 of a Rotifer, b, Brain; bl, excretory blad- 

 der; c, cloaca, the common opening of 

 digestive and reproductive organs; co, 

 PIG. 24. Spiral path of Paramo?- caelom; e, eyespot; ex, excretory canal; /, 

 oium. The figures 1, 2, 3, 4, etc., flame cells ;f.g, foot gland; ft, foot; g, gut; 

 show the successive positions oc- m, mouth; m.f, longitudinal muscle fibres; 

 cupied. The dotted areas with small mx, mastax; o, ovary; ph, pharynx, s.g, 

 arrows show the currents of water salivary gland; t, tentacle; tr, trochus, 

 draws from in front. (Jennings.) or cilia-bearing disc. (Galloway.) 



