48 
ORGANIC DEPENDENCE AND DISEASE 
ILLUSTRATIONS OF PLEURODICTYUM AND ITS COMMENSAL 
WORM HICETES 
Figs. 22 and 23. Top and side views of the corallnm in its normal size and form. 
The apertures of the worm tube are shown at X. 
Fig. 24. An etching which has the calcareous substance of the base of the coral 
removed and shows the initial convolutions of the worm tube. 
Fig. 25. The under side of a eorallum with the impression of the gastropod 
Loxonema hamiltoniae to which it was attached. 
Fig. 26. The form of the entire worm tube drawn from an actual specimen. 
Fig. 27. A shell of Loxonema hamiltoniae. 
Fig. 28. Vertical section of a eorallum, showing the convoluted worm tube. 
Fig. 29. Enlarged surface of a Loxonema shell which had been the base of 
attachment for the coral. This specimen bears several serpulid worm tubes 
which were there before the coral began to grow. 
Fig. 30. Section of the coral, showing tubes of more than one worm. 
