... s feed upon microorganism from the muck and water of the bottom and in turn are consumed by es, s and mankind. - Ann Haven Morgan

Different waters hold their own special communities; the dainty glen stream shelters companies of mayflies in its swift riffles; pond shallows and meadow brooks are the homes of lurking ; and wayside puddles are populous with mosquito wrigglers and . In all these places living things must contend with winter cold and summer drought, with storms and flood waters. In winter the pond populations drop to the bottom, frogs and turtles dig under mud and broken plants, whirligig beetles hide under banks to come out with every warm spell, and fresh water sponges are packed in tough covered capsules. In summer when its own pool dries up the water boatman flies to some other pond but many caddis worms burrow into the mud bottom and endure the drought as best they can.

No one who has lived by clear waters can have failed to see something of their wonderful life: minnows on the shoals; dragging their cumbersome portable houses over the brook bed; the young of mayflies clinging to the stones in the riffle; or the adult mayflies in their dancing nuptial flight in the air above the stream; and what could be more interesting?

At Kartabo the waters of the meet those of the and soon join the great lake-like flowing north through the low lying country of British Guiana until it runs into the sea at . These rivers are hedged in by the jungle whose undergrowth has invaded the border waters in a persistent attempt to gain more territory. roots swing so far out from the banks that fish swim in and out among them. Moccamoccas, the giant s, have grown out still further. Their clublike stems standing in close rank provide on gigantic scale the kind of animal shelter furnished in more modest form by our own and s. Many slow flowing creeks feed into these larger streams but their mouths are hidden by creepers, tangles of mangrove, and prickly shrubs, and if the currents are gentle enough they are choked by lush growths of .
… Even at Kartabo Point the daily tides are insistent reminders of the ocean forty miles away.The low tide lay bare stretches of muck and ooze, silt and silty sand ... the likely dwelling place of the burrowing and crawling Mayflies ...