"The white cone-like organ in the middle of the gills is the anus, and this animal was actually photographed in the act of defecating (the red-brown mass right at the top of the anus is the faeces, composed mostly of indigestible sponge spicules packed together with mucous)."
Comment from Richard Willan
The white cone-like organ in the middle of the gills is the anus, and this animal was actually photographed in the act of defecating (the red-brown mass right at the top of the anus is the faeces, composed mostly of indigestible sponge spicules packed together with mucous).