41 



POLYCH5ITA 



8. Arenicola. Mouth ; anus ; parapodia (very rudimentary) ; gills. 



9. Spirographis. Tube; parapodia; branchial filaments. 



10. Filograna (Serpulid). In 70 p.c. spirit, decalcify with weak nitric acid, stain in borax carmine 

 and mount in Canada balsam. Tentacles (modified palps); parapodia; thoracic membrane (fused 

 cirri) used in moulding tube ; individual budded off posteriorly. 



