The whight footed abalone also have the same clusters but they are fewer and they are not green, but cream or brown. The TEM sections reveal the structure of the clusters and it was evident that they are membrane bound and have a nucleus and also fairly large. Anyway there are numerous interesting facts about this pigment that don't yet give a satisfactory explanation of exactly what it is and how it comes to be there and only in some individuals. Here are some of my observations. Juveniles all start out being white with only larger adults being very green.
Some adults are white.
A hexane extract of the foot of green animals shows the presence of chlorophyll. When animals are kept in the dark for 2 months the colour doesn't diminish. It appears to be diet related because juveniles fed on brown kelp developed the colour whereas those fed red algae did not. Anyway that was just for interest. All I want to know is whether it looks familiar and if you have any insights.