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STARFISH GALLERY. 
the mosfc part parasitic, and infest plants as well as animals ; the 
common Round-Worms living parasitically in man (Ascaris, Stron- 
oylus, Trichocephalus) belong to this Order. Sometimes they are 
Fig. 14. 
Fig. 15. 
Fig. 16. 
Fig. 14. Diagram of the structure of a Turbellarian : ng, nerve- (cerebral) 
ganglia ; nb, nerve-branohes ; yg, yolk-glands ; t, testis ; o, ova ; ov, ovary ; 
c, cirrus ; m, mouth ; ph, pharynx. 
Fig. 15. Diagram of a Nemertine : 6, brain; m, mouth; n, renal organs; 
id, diverticula of intestine ; g, gonads ; sn, side nerve-trunk ; pr. proboscis in 
its dorsal sheath. 
Fig. 16. Diagram of the structure of a Nematoid ; m, mouth ; ph, pharynx ; 
a, anus ; o, orifice of genital tube. 
parasitic in their early stages and later live a free life — such are 
G or dim and Mermis. A specimen of a Mantid is exhibited from 
which half the body of the infesting Gordius has already protruded 
(Fig. 17). One of the most remarkable Gordii is the great elongated 
