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Records of the Australian Museum (2009) Vol. 61 
Figure 48. A-H, Spirobranchus arabicus (Monro, 1937): (A) tube showing the high median longitudinal ridge with fin-shaped sections. 
The latter may be high and long as in the posterior part of the tube figured, or consist of smaller low, fin-shaped processes as seen in its 
anterior part; ( B ) entire worm, showing the ventral side of the thorax; (C) dorsal view of the operculum of an older specimen; (D) dor¬ 
solateral view of the operculum of a juvenile; ( E,F) bayonet-shaped collar chaetae; (G) thoracic uncini; ( H) posterior abdominal uncini. 
