The beach was empty where I walked, except for bird tracks, tidal wrack, driftwood, bits of shell, or a finger sponge in evidence of the life alongside it, and depending on the warmth and receptivity to life that the season held, excepting also whatever microscopic animals might be crawling over wet surfaces around the sand grains. Again, emptiness, or poverty, is always qualified. After all the copepods, the nematodes or thread worms, and other groups unseen or unknown to me might be underfoot in vast numbers; and as I continued on there was no counting the number of little holes in the sand made by beach fleas or sand hoppers. As the autumn deepened I supposed they were unoccupied and deserted, since these beach dwellers, as I had heard it, should have been tucked away in their burrows by this time, with the door shut above their heads, waiting for March and April to bring a warm sun which could tease them out of dormancy. But one bright morning in the middle of November I saw a great many of them hard at work. At first I noticed thousands of little mounds on the surface of the sand in a strip some six to fifteen feet wide along the upper part of the beach, following in general the outlines of the previous high tide. Where a log or shelving bank was in the way, these mounds, and the many holes accompanying them, about knitting-needle size, were concentrated on the seaward side. I noticed that shore birds had attempted to pluck the occupants from their holes and had reached down two to three inches. I scooped out the sand where a hole was, spread it around, and revealed a little animal not over a half inch long, with two large eyes covering the sides of its narrow head. The eyes were not only conspicuous, they were also startlingly white; and the sand-hopper’s body flattened on both sides, was a mother-of-pearl, somewhat translucent. This odd creature, one of a family in the order of amphipods, is called _Talorchestia megalopthalma_, a title that gives special credit to its eyes. I put my pale-moon animal back in its hole, but to be held and thrust against its own volition apparently immobilized it, so I let it go free down the sands. After a second or two it made a few big and seemingly crazy hops--on sidelong springs like a toy--down a line of mounds and holes, popped into a hole and promptly disappeared.