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of the muscles, but it is usually more or less heart-shaped or globose, 
with a diameter of about 0,06 mm. Its position varies also. It may lie 
at the surface of the body, partly projecting through the genital pore 
Fig. 3. 
4—- 
Fig. 5. Diagram showing the origin of the 
ducts of the female genital organs. 1) Ovary; 
2) Receptaculum seminis; 3) Oviduct; 4) Lau- 
rer’s canal; 5) Yolk ducts; 6) Ootype; 7) Ute- 
rus; 8) Shell-glands; 9) Dorsal body-wall. 
Fig. 3. Vas deferens: diagram. 1) Vasa efferentia; 2) Posterior or thin-walled vesi- 
cula seminalis; 3) Anterior or thick-walled vesicula seminalis; 4) Papilla-like anterior 
end; 5) Valve-like fold. 
Fig. 4. Cross section of anterior vesicula seminalis. 
(fig. 2, 2), or it may lie dorsal to the genital pore and entirely enclosed 
in the genital sinus, in which case the genital pore is seen to be a small 
