Saw these on the beach in Long Boat Key last February. Still haven’t figured out exactly what they are. To me they look like pearls on the beach.. but they were soft.. maybe eggs ? egg cases? some other life stage of an organism? They made a really pretty trail on the beach… so that’s good enough for now.. 🙂
Photos of my World... 
They look awesome and I have seen theme as well, I think they are part of a seaweed plant.
thanks… that would make sense, there are always so many different types of seaweed and algae around!