Popular Science Monthly/Volume 55/June 1899/The Physical Geography of the West Indies: Reptiles and Fishes III
|THE PHYSICAL GEOGRAPHY OF THE WEST INDIES.|
By F. L. OSWALD.
III.—REPTILES AND FISHES.
THE present fauna of our planet includes many varieties of mammals and reptiles, and a few kinds of birds, that are found only on certain islands—a fact which seemed rather to justify the once universal belief in the origin of species by separate acts of creation.
A different theory of explanation has, however, been suggested by the discovery of fossil remains, proving the former existence of closely allied forms on continents where their battle for existence had to be fought against beasts of prey and competitors for a limited food supply.
The supposed products of an island genesis by the fiat of supernatural agencies, demanding recognition in mental penance and the payment of tithes, may thus be simply animal Crusoes, favored by the positive or negative advantages of their surroundings.
The dodo, in its struggle for survival, would have had no chance against South American tiger-cats. Not one of the twenty-odd species of Madagascar lemurs could have held its own against the competition of the African daylight monkeys.
Yet there was a time when night apes and large ground birds seem to have had things all their own way, the world over, and Central America may have afforded a chance for existence to several species of reptiles which at present are found only on the West Indian islands.
The Cuban bush tortoise (Eniys nigra) is found only in the forests of Santiago and Puerto Principe, and there only on the south coasts. It is the most sluggish creature of its genus, and does not seem to have had enterprise enough to crawl around the sand belt of Cape Maysi and colonize the jungles of the north side provinces. It is as helpless as a hedgehog, minus its bristles. The darkeys of the Cuban planters crack its armor with home-made hammers, and the tortuga prieta, or prieta, as they call it for short, forms a factor of holiday menus as frequently as 'possum pie in southern Georgia.
Swift-flowing rivers bear it away as they would a floating log, and it is wholly incredible that its ancestors should have crossed the Caribbean Sea in quest of a more congenial home; but it is possible enough that its eggs may have been ferried across on one of the driftwood islands which the Sumasinta River often tears from the coast swamps of southern Mexico and carries into the current of the Gulf Stream. The evolution of the South American giant cats was probably the death warrant of its continental relatives, but in Cuba it had no four-footed enemies except the hutia, or jungle rat, that now and then destroys its eggs.
An equally favored islander is the grayish-yellow rock lizard, abounding in the uplands of Cuba and Hayti. The lizard-killing cranes of Honduras have not found their way to the Antilles, and the lagartilla still basks in the sun that once smiled upon the indolence of the naked Lucayans.
The toco, or Cuban hornbill, however, devours small reptiles of all sorts, and the West Indian tree lizards have become almost as nimble as squirrels. They dodge behind branches and wait to ascertain the origin of every flitting shadow, but from imminent danger save themselves by a swift descent, followed by a bold leap into the thickets of the underbrush. Their courtship is quite as grotesque as that of the strutting bush pheasants. The males will swing their heads up and down and puff up their throat-bags till their skin seems on the point of disruption, while the objects of their rivalry sit blinking, reluctant to risk an open manifestation of preference. Some gorgeously beautiful varieties are found in Jamaica: greenish-blue, with a metallic luster, and rows of bright crimson spots, as if the design of protective colors had been patterned after the flower shrubs of the tropics.
The word iguana is of Mexican origin, and rarely used in the Spanish West Indies, but the animal itself is—for culinary purposes, though the Haytian negroes do not go quite as far as the mongrels of Yucatan, where iguana farmers fatten the defenseless reptiles with cornmeal, in wickerwork baskets, that are brought to market as a New England poultry fancier would fetch in a crateful of spring chickens. But, prejudice aside, there is no harm in an iguana fricassee; the meat is white and insipid, but takes the flavor of every spice, and is far more digestible than such hyperborean delicacies as. fried eels and pork fritters. There are two species—one in eastern Cuba, with spines all the way down to its tail-tip, and in Hayti a smaller one, with a smoother tail, but with an exaggerated throat-bag and wattles like a turkey gobbler.
Lagartos vastecos, or "tree alligators," the Cuban Creoles call the scampering forest dwellers, that attain a length of four feet, and can stampede foreigners by leaping to terra firma with an aplomb that scatters the dry leaves in all directions. If chased, they will take to water like frogs. They are first-class swimmers, their throat-bag serving the purpose of a float, and once in the ripple of the stream are hard to keep in sight, as they have a trick of keeping their legs close to the body and navigating by means of their submerged tails. Like the rainbow hues of the coryphene (miscalled dolphin), the bright colors of the iguana soon fade after death, and the shriveled greenish-brown specimens of our taxidermists give no idea of the appearance of the living animal in the sunlight of its native land. The Iguana tuherculata (eastern Cuba) is velvet-green above, with saffron flanks, ringed with blue, black, and brown stripes, and the pet specimens, basking on the porch of a coffee planter, can challenge
comparison with the paroquets that flutter about the eaves of the outbuildings like swifts around a martin box.
Cuba has also acclimatized a horned frog, and one species of those curious half-lizards whose shapes may have suggested the dragon fables of antiquity. The "basilisk" (Cyclura carinata) is only half a yard long, but can erect its crest and raise its pronged tail in a manner that will make a dog leap back in affright. It has no goiter-bag, but the skin of its throat is elastic, and can be made to swell out like that of the East Indian cobra, while its multiplex spines vibrate ominously. The little monster is, nevertheless, one of the most harmless reptiles of the tropics, and subsists on succulent leaves, with occasional entremets of small grubs and insects. In that case, however, Nature has rather overdone its efforts at protective ugliness, and the Creoles kill the poor simulator of terrors as the Mexican rustics would a horned toad.
A plurality of the zoölogical immigrants of the West Indies seem to have come from Mexico, and it is a suggestive fact that the number of reptiles steadily decreases from west to east. Cuba, with its western headland approaching the east coast of Yucatan, thus came in for a lion's share of lizards, tortoises, and ophidians.
Hayti, though only one fourth smaller, experienced a seventy-five-per-cent discount, and all natives and travelers agree on the curiosum that there is not a single species of serpent on the island of Porto Rico. Trinidad, with an area of only fifteen hundred square miles, but laved by the giant current of the Orinoco, boasts twenty-eight species of land serpents, besides several pythons and swamp vipers. The Trinidad museum of venomous ophidians does not, however, include the dreaded fer-de-lance, which infests the woods near Samana Bay on the south coast of San Domingo. The Bothrops lanceolatus is larger than a rattlesnake, and its bite, though not always fatal, causes fearful inflammation, but its aggressive disposition has been greatly exaggerated. Like most venomous serpents, it is a sluggish brute, relying on its ability to crouch motionless till its prey comes in range, then get in a snap bite and shrink back to wait till the virus begins to take effect, and the victim, in its fever spasms, betrays its helplessness by those eccentricities of conduct which are apt to be misinterpreted by the dupes of the "serpent-charm" superstition.
The fer-de-lance is found also on the islands of Martinique and Santa Lucia, where the natives counteract its virus with a decoction of jungle hemlock, and the basis of its grewsome reputation seems to be the fact that it does not warn the intruders of its haunts, after the manner of the cobra or the rattlesnake, but flattens its coils and, with slightly vibrating tail, awaits events. If the unsuspecting traveler should show no sign of hostile intent he may be allowed to pass unharmed within two yards of the coiled matador, but a closer approach is apt to be construed as a challenge, and the vivoron, suddenly rearing its ugly head, may scare the trespasser into some motion of self-defense—he may lift his foot or brandish his stick in a menacing manner. If he does he is lost. The lower coils will expand, bringing the business end, neck and all, a few feet nearer; the bead "points," like a leveled rifle, then darts forward with electric swiftness, guided by an unerring instinct for the selection of the least-protected parts of the body.
And the vindictive brute is ready to repeat its bite. For a moment it rears back, trembling with excitement, and, if felled by a blow of its victim's stick, will snap away savagely at stumps and stones, or even, like a wounded panther, at its own body.
A very curious adaptation of means to ends in the modification of the virus is its swiftly fatal effect on birds. A stricken child, though half crazed with fear, may run a distance of three miles before paralysis begins to impede its motions; a squirrel will escape to its nest in the top of the tree, only to come forth again and topple down
in its delirium; but a bird drops as if he had swallowed a dose of prussic acid. Serpent virus is specifically a bird poison; in other words, it acts instantaneously in cases where a few moments' delay would defeat the purpose of the snap bite. Wounded rodents will not run very far and can be relied upon to come out of their holes; but a bitten bird, unless promptly paralyzed, would fly out of sight and drop in distant thickets, beyond the ken of its destroyer. And of all bird-killing reptiles the fer-de-lance is the most destructive. The Spaniards have varied its bill of fare by importing the wherewithal of an occasional rabbit stew, but during the preceding ages it had to subsist on poultry, like a popular circuit preacher—the hutia rat having developed a talent for avoiding its haunts.
The alleged horror naturalis of serpents is perhaps not more deep-rooted than the aversion to cats; at all events, the West Indians have overcome it sufficiently to prefer rat-killing snakes to tabbies. In thousands of rancho cabins a pet serpent of the genus coluber may be seen gliding noiselessly along the rafters, or slip through the crack of a floor plank to reach the penetralia of the basement, where the death shriek of rodents soon after announces the result of its activity. Aristocratic creoles relegate it to their stables, but the tenants of numerous backwood casuchas furnish it a cotton-stuffed bed box, and reward its services with a weekly dish of milk. There are several species of large river serpents, and one true boa, the Cuban matapollos, or chicken-killer, that attains a length of eighteen feet, and has been known to use its supernumerary coils for the purpose of cracking the ribs of a hound flying to the assistance of the barnyard rooster.
In addition to the above-mentioned jungle tortoise there are several land turtles of the genus chlemmys, and thousands of chelidonians are annually caught on Samana Bay, southern Porto Rico, St. Vincent, the Isle of Pines, and the north coast of Matanzas, Cuba. Those of Santiago Bay have gradually been exterminated, but a large number of West Indian fishing waters are practically inexhaustible. A specialist like Agassiz might haul nondescripts from scores of Haytian coast rivers, and the angle fishers of the Cuban sierra brooks can hook an equally interesting reproduction of an Appalachian species.
"Some of our companions had to eke out a haul with crawfish," says the traveler Esterman, "but our own string of sundries included a puzzle for naturalists. We had caught some twenty brook trout, absolutely indistinguishable from the species found in the head waters of the Tennessee River. Where did they come from? Had they crossed the Gulf of Mexico and ascended the rapids of half a hundred rivers, or had Nature copied her own handiwork in such details as the small dark dots below each red spot, and the occasional breaks in the lines of the silver-white keel streaks?"
The perch of the forest rivers include several nest-building varieties, and the sportsmen of Kingston, Jamaica, often amuse themselves with target practice at a species of rock fish that come clear out of the water and bask, like coots, on the harbor cliffs.
With every mile farther south the number and variety of the finned aborigines become more infinite, and the fishermen of the estuary of San Juan de Porto Rico alone catch pompanos, mullets, cavalli, red snappers, chiquillos (a kind of sardelles), sea bass, dorados, skip-jack, angelfish, skate, ray, sheepshead, garfish, torpedo-fish, devilfish or giant ray, cobia, hogfish, croakers, shark, and coryphenes.
The tiger of the sea, the great white shark, occasionally visits the harbor waters of Cuba, and has been known to seize barefooted peons, surf-bathing horses in the next neighborhood of Morro Castle, and drag them under so suddenly that their companions were unable to account for their disappearance till the foam of the breakers became flecked with blood.
That champion of marine man-eaters is as smooth as a hypocrite, and hides its double row of horrible fangs under a slippery nose, while the little butterfly fish tries its best to disguise its helplessness with a crest of spiny fins. Its length rarely exceeds four inches, and it can be handled with impunity, but its spines are just rigid enough to entangle it in tufts of gulf weed, and in company of equally tiny sea horses and goldfish, it can often be seen in the aquariums of the Jamaica seaport towns.
[To be continued.]