WHILE on the point of taking my accustomed morning plunge in one of the clear pebbly streams that find their way into the plains from the northern mountain ranges of the island of Trinidad, my attention was attracted by the eccentric movements of a small fish of the perch tribe. In general this fish is extremely shy, scudding off into deep water or under some overhanging bank on the approach of man; on this occasion, however, on putting my hand into the water, the fish, to my astonishment, darted forward again and again, striking my hand with considerable force. Rather at a loss to account for such temerity in a fish only 4 in. long, I watched its movements narrowly, and at last found out the cause. In a small hollow close by, about the size of half an egg, artistically excavated from the bright quartz sand, a multitude of tiny fish were huddled together, their minute fins and tails in constant motion. They had apparently been only very recently hatched, and were no larger than common house flies; the parent fish kept jealous watch over her progeny, resenting any attempt on my part to touch them.