Over the past ten years, I have accumulated a huge cache of shells from my annual visits to Port Aransas but what’s on the beach there is unpredictable and never the same day to day let alone year to year. Sometimes what washes ashore is a single variety of shell, sometimes a few different kinds, sometimes they’re whole, mostly they’re broken. On some days, there are no shells at all on the beach. On my first visit to the beach last week, the tide was exceptionally low and the sand looked smooth and as if there were no shells at all. When I got near the water, I could see that there was mostly one kind of shell, the tiny coquina. It’s a small clam, no more than a half inch, with shells in all kinds of colors. When they’re just a shell, and the clam is gone, they lay on the sand looking almost like butterflies.