FANG AND POISON

Waikato Times, Volume 116, Issue 19314, 21 July 1934, Page 14 (Supplement)

FANG AND POISON

Poison is to some animals what teeth and claws are to others. It is [ if anything a more effective instrui men! of combat, and one which pro- 1 1 vides many otherwise defenceless ! creatures with a sure means of lidding their own (says the Manchester Guardian). Not long ago there arrived at the London Zoological Gardens a eonj signment of snakes whose specially is I spilling poison. Such is their mastery of this accomplishment that motor goggles have lo lie worn by those who lend them to protect Hie eyes, which appear lo lie a favourite target, A notorious offender in this respect is Ringhal’s snake, a South African species gifted witli uncanny marksmanship. Many people still imagine that the power'of spitting poison is general among snakes and oilier reptiles, but this is as much a fallacy as the belief that the flickering forked tongue is a poison “fang.” A similar act, though performed in a totally different way, has made the skunk notorious and secure from attack, for no adversary will voluntarily face the stream of fetid fluid which this animal can emit. After holding amphibians like toads and salamanders a milky fluid is ofen observed on the hands. This issues from the glands which may be either distributed all over the skin of the body or localised jn the form of warty excrescences. The substance Is not 'poisonous to man, but merely disagreeable, and in some cases mildly irritant. Injected into the circulatory system of animals it may, however, prove exceedingly poisonous, affecting the heart and the nerve centres. That of a South American amphibian , is employed by the Indians lo poison their spears and arrows for killing monkeys, in the same way that the Bushmen utilise the venom of the paiffadder. Mechanism of Fangs. Lethal weapons designed to inflict a direct flesh wound occur chiefly among reptiles and insects. Snakes can be roughly divided into venomous and non-venomous species; but as there arc no common characters by which to distinguish the one from the other it is policy to regard all as suspect. 'Phe simple but terribly efficient mechanism of a snake’s poison apparatus can be explained in a few words. In lhe great majority of cases the fangs arc two large backward-curved teeth near flic front of lhe 'Upper jaw. An ingenious hinge allows them lo lie flat when the mouth is-closed and to spring erect as it opens. The pressure of biting causes lhe poison, a modified saliva, contained in glands near lhe eyes, to pass into Hie wound by way of Hiese specialised Icclli. To make this possible each tooth lias eillicr a groove on its- front, side or a narrow canal through ils interior along which the poison travels. In the latter case the aperture of the canal is to one side of the tooth, a little below the point, exactly as in a hypodermic ‘syringe. This lessens the liability to blockage and enables the extremity of the tooth to continue on a fine point. Sometimes the fangs get broken, but there are always reserve teeth ready, or nearly ready, to take their place. Venon is a yellowish fluid, usually odourless and tasteless, and possessing remarkable properties. It can be frozen or dried without losing potency,

How They are Made Use Of. Defence of Animals,

and in some cases no harm results from swallowing it. The effects of snake-bite vary greatly. Different kinds of animals react in different ways lo the same kind of poison. Some are completely immune from its action and, in fact, prey upon snakes. The secretary bird is an example, and also the king cobra, or hamadryad, which feeds exclusively upon other snakes. Insect Stings. The poison weapons of insects can he viewed with less concern, for, as a rule, the most human beings suffer from them is acute discomfort. Diseases communicated by insects are due to bacterial infection following a bile, and not io the sling. Although commonly used defensively, the power of inflicting a wound and introducing poison is employed by many insects as a means of securing prey. Generally lhe poison consists of formic acid mixed with other irritants, and it is ejected by muscular contraction through a complex piercing organ, or sting, at the end of the abdomen. And since this sting appears to have been derived from the egg-depositing organ (ovipositor) it follows that only females are in possession of it. Drones, or male bees, for example, have no stings. Many insects have what looks like a dangerous sting at the hinder end of the body. No alarm need be felt concerning this, because stings are not advertised in this way, but discreetly hidden. Such appendages are harmless ovipositors designed to penetrate crevices or act as drills. Every year consternation Is caused by the appearance of a largo insect of the size and colour of a hornet which is brought to this country In imported timber. It is armed with a formidable-looking instrument, nearly an inch in length, and is often slaughtered and sent to the local museum for identification. Tills is a giant sawfly and the supposed sling is an innocent ovipositor. Hunting wasps possess remarkable power to control the action of their poison. These insects capture living caterpillars and other insects, and store them in a chamber as ready-lo-hand food for llicir young grubs, which share the same apartment. But first of all the prey is stung, not in a haphazard fashion, but scientifically by one or more thrusts of the sting in various parts of the body. The result is not death but general paralysis, lhe effect, of which is to render Hie victim inactive and therefore unable lo molest the tiny grubs. In this state it may live for weeks to provide a larder for the growing family. Legs and Spine. Various slrnclures of the body Pave, by modification, come to function- as poison weapons. In centipedes it is Hie first pair of legs that are so developed. These are clawlike and have at the tip an opening communicating with a poison gland. Some of the tropical species aTe a foot in length and are able to inflict a “bite" which may be fatal to man. Scorpions carry at the end of the long flexible body a stout spine supplied with poison generated in the swollen terminal segment of the body. The curved shape of the spine appears a little curious until it la realised that the creature arches its tail over its body and strikes forward at the prey, which is held in front of the head by the great pincer-llke claws.