In a follow-on email, Blair included this photo of two blue glaucus feeding on a by-the-wind, and this additional information: Search where the recent swash lines are pushed up. On the beach, Glaucus are puckered up like individual bright blue peas. All that we found (~10) were alive and unfolded gloriously when placed in seawater.
Our thanks to Blair for sharing his photos and his knowledge, and especially for his ability to describe a glaucus as a bright blue pea! As we've said many times before, Blair and Dawn's book, Florida's Living Beaches: A Guide for the Curious Beachcomber, is a must-have.