Colour variations within a spawn-mass may be due to combination of egg-strings from several individuals.
Copulation lasts several hours or even days. Egg string is extruded intermittently in sections (Eales, 1921), each section curls, resulting in tangled mass. Colour changes with time, so sections of string issued at different times by a single individual may have different shades from each other with abrupt colour changes corresponding to pauses in laying. The cream section right-of-centre is thinner than other sections, suggesting that it is the most recently laid with least time to absorb water to expand.

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