Most pitiful of all was a tiny opossum, with a single young one clinging tightly about her neck, which approached as I was about to leave. She was marooned on a hollow log which revolved in an arc while it drifted. As it turned, the little mother climbed, creeping first upward, then turning and clambering back, keeping thus ever on the summit. The tail of the baby was coiled about her mouth, and he was clinging with all his strength. It was a brave fight and well deserved success. No boat was in sight, so I could not hesitate, but, pulling off my shoes, I waded out as far as I could. At first I thought I must miss it, for I could not go in to my neck even for an opossum. But the wind helped; one or two heavy waves lapped conveniently against the sodden bark, and I succeeded in seizing the stub. As I reached for the little creature, the young opossum gave up and slipped into the water, and a ripple showed where a watchful fish had snapped it up. But I got hold of the mother's tail, and despite a weak hiss and a perfunctory showing of teeth, I lifted her and waded ashore. The last view I had, showed her crawling feebly but steadily along a branch into the heart of a dense thicket. I climbed back to my outpost and dried my clothes in the sun, meditating on the curious psychology of a human which wanted opossums and would unhesitatingly sacrifice a score of opossums for a real scientific need, and yet would put itself to much discomfort to save a single one from going out to sea. Sentimental weakness is an inexplicable thing, and I finally made up my mind--as I always do--not to yield again to its promptings. In fact, I half turned to go in search of my specimen--and then didn't. The tide had reached full ebb and the sun was low when I started back, and now I found a new beach many feet farther out and down. Still no shells, but a wonderful assortment of substitutes in the shape of a host of nuts and seeds--flotsam and jetsam from far up-river, like the snake and ants and opossum. There were spheres and kidney-shapes, half-circles and crescents, heads of little old men and pods like scimitars, and others like boomerangs. Some were dull, others polished and varnished. They were red and green, brown and pink and mauve, and a few gorgeous ones shaded from salmon into the most brilliant orange and yellow. Most were as lifeless in appearance as empty shells, but there were many with the tiny root and natal leaves sprouting hopefully through a chink. And just to be consistent, I chose one out of the many thousands piled in windrows and carried it high up on the shore, where I carefully planted it. It was a nut unknown to me at the time, but later I knew that I had started one of the greatest of the jungle trees on its way to success.