We have two types of whelks in our parts, the channeled and the knobbed. They reproduce via a string or chain of egg capsules, which is anchored to the sand. Often, however, the chains end up washed ashore: If you're me, you knew this already. This is one of the segments of the chain above: I learned last week, after a lifetime of seeing these things on the beach, that each of these segment is filled with baby (1/8 inch long) shells:
Perhaps two dozen in each segment. Wonders will not cease.