Popular Science Monthly/Volume 48/March 1896/The Coming of the Rains in Guiana
By JAMES RODWAY.
WE are nearing the end of November, and the rains have come. For three months no more than one or two passing showers have fallen, and every tree and shrub in our gardens has done its best to accommodate itself to the changed conditions. During the rains of May, June, and July they grew rampant, the climbers extending themselves in every direction for long distances. Then came a severe check. The burning sun poured down on the parched earth at the beginning of September and caused most of the trees to flag and hang limp. Some of the more delicate plants in the garden had their leaves burned at the edges and for a time they looked unsightly. Some commenced to drop their leaves preparatory to a partial rest, but these were few; the majority braced up, as it were, and soon adapted themselves to the altered situation. The change was characterized at first by a wealth of flowers, but these quickly disappeared, until hardly a blossom could be seen. As the foliage grew less dense, the young fruit became conspicuous, and very soon guavas began to ripen and mangoes to set. Now also the mammee apple, which matures its fruit only once a year, felt the influence of the sun and came to perfection.
As month after month passed, the leaves fell until the canopy was almost bare, and in one or two cases toward the end of the dry weather the trees became denuded for a few days, or, in the case of the fiddlewood and silk cotton tree, several weeks. Those trees which never become quite bare dropped leaf after leaf until when the proper time came the young foliage pushed off the few leaves that remained and took their place.
Now comes the rain. The heat has been more oppressive than usual, and the sun is often obscured by thick clouds. Distant thunder is heard, and to the west and south the black clouds are lowering. Now and again great splashes of rain fall suddenly and as suddenly cease. Walking along a straight road, you see a mist apparently rising half a mile away, and when you come to the spot find that the rain has well soaked the road for a short distance. Then you may see a similar mist over a cane field, and notice that it is rolling steadily toward you. Listening, you hear a clattering, as if a regiment of cavalry was galloping along the road, and in a few seconds look for shelter against the big drops. It comes, wets you to the skin, and passes on up or down the road, leaving you very uncomfortable, but brightening up the vegetation and rousing the birds from their siesta.
These are the preliminary skirmishes, as it were. The rains have not yet come only their vanguard. Presently they will be down in force to soak the parched earth and make every tree and shrub rejoice and blossom.
During the drought, animal life has been almost quiescent. Butterflies, moths, and beetles have been dormant as chrysalids. The foliage has hardened and lost its luscious taste; it would be therefore undesirable that larvae should be hatched at such a time. Ants have been busy as usual, however; their nests may be seen in the dry ground everywhere. Frogs hide themselves in cracks of the earth or crawl into the mud at the bottom of the almost dry canals. Spiders, centipeds, scorpions, and cockroaches go outside the house only to come back when the ground is sodden. A few flowers come up on the roadsides as the dense thicket of sour grass becomes less rampant, but toward the end of the season the parapets look almost bare.
Yesterday a heavy downpour closed the cracks in the dry ground and flooded some of the ants' nests in the garden. Today a regiment of great black ants is marching up the sides of the open gallery, and here and there one is running over the floor. Three quarters of an inch long, these creatures look rather formidable, but they are not vicious, nor is their nip painful. Out in the garden, however, a swarm of red fire ants is moving house, and if you happen to tread on the procession the mistake is very soon brought to your notice by sundry pricks and instillations of venom on your lower extremities. Then there are the tree ants, who make little nests the size of walnuts and keep flocks and herds of scale insects on the under surfaces of the leaves. For months their live stock has consisted mainly of hard scale insects; now they are busy fostering the young of these and bringing forward species of a softer nature. Some of these stockbreeders build their small nests about the roots of plants and thus escape the flood, while those who nest in the bushes seem to have gone a step further in their development.
At this time also the small black ants are everywhere. They come into the rooms and get upon our dining table, even though its legs are placed in pans of kerosene oil. A chair will provide a suitable gangway, or they will even run over your clothes as you sit at dinner. They even get into our beds, and we wake up at night to find hundreds of these tiny creatures crawling over us and giving vicious bites here and there. Then the baby cries in the next room, and its nurse wakes up to find the little pests running over its face and sucking the moisture from its eyelids. The child wakes up and rubs the part with his fist, to be rewarded with sundry bites on his delicate skin. Or perhaps one of them has got into his ear, and the child screams with all his might; then the mother or nurse has much ado with a syringe and oil before silence is again restored.
Now come the cockroaches. Not that they have ever been entirely wanting, but as long as the weather was dry they could hide under heaps of dead leaves or about the roots of trees in the garden. Routed from these snug quarters, they appear in great numbers, flying into the open sitting rooms, and perhaps making a lady scream out with disgust as one of them sprawls on her dress. Their object is to hide themselves as soon as possible, no matter where, and female drapery is very convenient. Like the ants, these stinking creatures invade our bedrooms, and a newcomer is warned not to sleep with his mouth open, for he might wake to find one exploring the cavity. Those who have lived in the tropics for any length of time can hardly escape tasting the cockroach. Now and then they run over our dishes and leave their taste and smell behind, while occasionally one gets into the flour barrel and spoils your cake or pudding. We have seen bits of their carcasses in our bread, and have had to reject a roll altogether from such a cause.
Now that the ground is well soaked, the wood ants or termites begin to swarm. They fly for a little while, but quickly get rid of their wings, to crawl into the chinks and crannies of the floor, between the covers of books, and in fact everywhere. They litter the tables with their cast-ofl wings, and if not looked after will do serious damage in a few days. Furniture is bored with holes, books are excavated to provide nests, and the very house itself becomes ultimately little more than a home for wood ants. The boards appear to be uninjured, but you can almost put your finger through them on account of the numerous channels and excavations of these apparently helpless little creatures.
The hardback a black, chaferlike beetle is very conspicuous after the rains have drenched the ground. They pass their larval stage in the earth and are driven forth in myriads. Not so disgusting as the cockroaches, they are yet very troublesome. They fly to the lights in your sitting room and drop upon your book as you are reading, or inside your collar. As for the ladies, they seem to be peculiarly open to such crawlers, as they have so much drapery, but the Creoles take hardbacks almost as a matter of course. We remember, however, one occasion at an evening entertainment when these beetles spoiled half the pleasure of the female part of the audience. They came in literally by thousands, and, flying in their blundering way at the gaslights, fell upon the people below. Evening dress was worn by the ladies, and this made the matter so much the worse. Some shuddered as they felt them crawling over their bare necks, and there was a continual movement of the hands to pick them off. When we state that the beetles were swept up next morning by pailfuls, some idea can be formed of their number.
Moths also appear in great numbers at this time. The flowers open, and those that are nocturnal perfume the air, bringing the insects to your garden. The white flowers shine in the darkness, but not so brightly as your gaslights, and it follows that many a sphinx comes in and commits suicide. Smaller insects also appear, so that what with one and another a table under the lamp is littered with hundreds of the dead and dying before you go to bed.
As these come indoors, some of their enemies follow. Centipeds, scorpions, and spiders leave the garden and look for the luscious cockroach in his new quarters. Web-making spiders are not very conspicuous, but those which hunt veritable beasts of prey lurk in every corner. To see one of them spring upon a cockroach is as interesting, perhaps, as the attack of a tiger upon an ox. And, when the spider has taken all he wants, the ants come and carry off the remainder. There they go, marching up the wall, a hundred tiny creatures carrying between them the monster corpse, probably weighing more than a thousand of its bearers. We have often wondered at such a sight, and thought of the difficulty of carrying a heavy weight under such circumstances.
Not only are nocturnal insects roused by the rains, but the butterflies also come forth from their chrysalids. We have an Aristolochia pida climbing up the gallery which has been seriously checked by the continual attacks of one particular species. It is a handsome creature, with black wings edged with yellow. As the rains fall, the plant puts out new shoots, and almost immediately the leaves and stems are dotted with yellow eggs. The butterflies come into the open gallery sometimes three or four at a time, and refuse to be driven off until they have done their work. In two or three days the caterpillars are at work, and with all our attention the plant is often quite denuded.
The frogs come forth from their hiding places as the canals become filled, with their rejoicing croak and hubble-bubble. Toward evening another species chirps and makes up to some extent for the absence of singing birds: in fact, it has been called the Demerara nightingale. After nightfall fireflies swarm over the marshy places, twinkling like myriads of stars, and they sail here and there in search of prey; for, of course, the gnats and midges and mosquitoes are at hand in such places. They also come into the house occasionally, but not in great numbers.
We have read of fireflies glancing through myrtle boughs and lighting up the dark arches of the forest, but rarely indeed do we see them among bushes, and never in the virgin forest. Their prey can not be found in such places. Over a marshy spot, however, they dart by thousands, each for an instant shining forth and as quickly hiding its light. Here, also, mosquitoes swarm, to pounce upon the unlucky wanderer who goes " mooning "about after dark.
In our garden the ferns are suddenly infested with caterpillars. The young and succulent fronds are delicate morsels, and as the rain brings them forth their enemies come to the front. Yonder pretty specimen of Adiantum farleyense was pushing out three delicate croziers yesterday; now they are nothing but bare stalks, while the fat green larva which has done the mischief hides behind one of them. Snails also appear from you know not where, to get a share of the succulent young shoots, and grasshoppers follow to almost denude a plant of leaves during the night.
Under the arc lights on the street are scattered hundreds of beetles, and round them hover great batlike sphinges, impatient to destroy themselves. Prevented from getting inside the globes, they dash themselves against the barrier, to fall or go off at a tangent. As you stroll along in the moonlight, the odors of a thousand flowers are wafted from the neighboring gardens, and the buzz and hum of insect life show that other living things are attracted by the efforts of the flowers. Yonder is a white convolvulus, its flowers showing up against the dark foliage like little moons. It does not emit any perfume, for its size and color alone make it conspicuous. Here is an avenue of fiddlewood trees, the flowers of which can not be seen, but the almost overpowering odor they emit is quite as effectual as the color of the convolvulus.
You would like to classify these odors. Some are very grateful, others cloying. There is the jasmin type, which, when excessively strong, is sickly. Then comes the West Indian mignonette, which is not unpleasant at a distance, but which is almost nasty in a room. The most grateful to our sense of smell appears to be an odor in which there is something spicy this never cloys. On a damp evening all these come at intervals, now as light zephyrs and anon in overpowering bursts of perfume. Then there are odors too delicate for appreciation by our gross organs, which nevertheless attract insects from long distances. As the flowers open, the visitors appear, to linger round for an hour or two perhaps in the morning and then vanish until the same time next day.
Why do particular species of butterflies and moths confine themselves to one plant? Our plague, the butterfly above mentioned, comes to lay its eggs on or near the AHstolochia, but on no other plant. A day or two ago we found its larvae on some seedlings about two inches high, and there is one plant which vainly attempts to push out new shoots, for as soon as a green leaf appears it is eaten. But the insect does not always lay its eggs on the leaves or stalks of the plant, but rather chooses a railing of the gallery or a portion of the latticework, always, however, in the immediate neighborhood of the food plant. Is not this the act of a reasoning being rather than hereditary instinct?
The effect of the rainfall on our niagnificent vegetation is wonderful. What immense quantities of water ai^e stored in the great herbaceous plants of the tropics the banana, maranta, and the treelike papaw! All these are softer- wooded than many of the delicate plants of other climes which grow only to a few inches above the ground. With such a wealth of light and moisture, ever} thing rises toward the sun. Daisies and primroses would be smothered; there is no room for them except up in the trees among the epiphytes. Your gardens, fields, and even woods are but miniature representatives of ours only comparable to the contents of a box of Dutch toys. Grasses often rise above our heads, and the cousins of your Compositce, become tall shrubs. There are no BanunculacecB, Primulacece, or Umbelliferfv , and the
VOL. XLVIII. 47 violets are almost trees. Nothing but rampant grasses and sedges in the meadows, a few coarse, weedy flowers on the roadside, a wealth of vegetation in the canals, and everything else bushes and trees. No delicate plant hugs the ground for warmth, but all shoot upward, only requiring the heavy rains to enable them to rise higher and higher.