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See also:SCORPION (See also:Lat. See also:Scorpio) , the See also:common name for members of the class See also:Arachnida (q.v.), distinguishable at a glance from all the other existing members by having the last five segments of the See also:body modified to See also:form a highly flexible tail, armed at the end with a sting consisting of a vesicle holding a pair of See also:poison glands, and of a See also:sharp spine behind the tip of which the ducts of the glands open . Like See also:spiders they have four pairs of walking legs; but the limbs of the second pair form a couple of powerful pincers, and those of the first pair two much smaller nippers . They feed entirely upon See also:animal See also:food, principally upon See also:insects such as beetles or other ground See also:species, although the larger kinds have been known to kill small lizards and mice . The large pincers are studded with highly sensitive tactile hairs, and the moment an See also:insect touches these he is promptly seized by the pincers and stung to See also:death, the See also:scorpion's tail being swiftly brought over his back and the sting thrust into the struggling See also:prey . See also:Paralysis rapidly follows, and, when dead, the insect is pulled to pieces by the small nippers and its soft tissues sucked into the scorpion's mouth . Scorpions vary in See also:size from about r in. to 8 in.; and the amount of poison instilled into a See also:wound depends principally upon the size of the animal . But the poison is more virulent in some of the smaller than in the larger species . Upon mankind the effects of the poison are seldom fatal, though death has been known to follow in the See also:case of patients in a poor See also:state of See also:health at the See also:time . In small scorpions, like those belonging to the genus Euscorpius, which occurs in See also:Italy and other countries of See also:South See also:Europe, the sting is said to be as See also:bad as that of a See also:wasp; but in many tropical species acute See also:pain, accompanied by inflammation and throbbing of the wounded See also:part, follows . But unless molested, scorpions are perfectly harmless, and only make use of the sting for the purpose of killing prey . The belief that scorpions commit See also:suicide by stinging them-selves to death when tortured by See also:fire is of considerable antiquity and is prevalent wherever these animals occur . It is nevertheless quite without See also:foundation in fact; for it has been proved experimentally of See also:late years that the venom has no effect upon the individual itself, nor yet upon a member of the same species . Scotpions, however, are extraordinarily susceptible to See also:heat, and succumb very rapidly when exposed either to the warmth of a fire or to that of the tropical See also:sun . Moreover, when they feel the heat beating upon them they brandish their tails and strike right and See also:left as if to drive off or destroy the unseen enemy; and there can be no doubt that the belief above alluded to is traceable primarily to observation of the sequence of events just described, the final event being the death of the animal, not, however, from a self-inflicted wound but from the heat which provoked the behaviour suggestive of suicidal purpose . It may be that under such circumstances a See also:random stroke has now and again wounded the animal itself; but a wound so inflicted' would be accidental, not intentional, and at most would contribute in a small measure to the creature's death . Scorpions are very easily rendered innocuous by scraping off the sharp point of the sting; and specimens, which are handled with impunity by See also:Arabs and Dervishes to impress the uninitiated with their super-human attributes, have generally been treated in ° a Scala this way . At the ~ 1 IG~chu See also:African Scorpion (Pandinus heros). same time it has been shown that insensibility to the pain of the sting and See also:immunity to the See also:ill effects can be acquired by any one who has the courage to permit himself to be repeatedly stung . Like many poisonous animals, scorpions are for the most part rendered conspicuous by distinctive coloration of See also:jet-See also:black or black and yellow; and many of them are gifted with stridulating See also:organs, See also:developed in various parts of the body which are functionally comparable to the rattles of rattlesnakes, porcupines and other noxious animals . In habits scorpions are cryptozoic and nocturnal, spending the daytime concealed under stones or fallen See also:tree trunks or in burrows, and only venturing out after sunset in See also:search of food . Amongst the burrowing kinds are the large African species belonging to the genera Pandinus and Opisthophthalnzus and to the eastern genus Palamnaeus . The yellow scorpions of the genus Butkus, which are common in See also:Egypt and the See also:Sahara, lurk on the See also:watch for prey in shallow depressions which they excavate with their legs in the See also:sand . Unlike the See also:majority of Arachnida, scorpions are viviparous . The See also:young are See also:born two at a time, and the brood, which consists of a dozen or more individuals, is carried about on its See also:mother's back until the young are large and strong enough to shift for themselves . The.young in a See also:general way resemble their parents and undergo no See also:metamorphosis with growth, which is accompanied by periodical casting of the entire integument .
Moulting is effected by means of a split in the integument which takes See also:place just below the edge of the See also:carapace all See also:round, exactly as in See also: Moreover, the occurrence of closely related forms in Australia and South See also:America on the one See also:hand, and in tropical Africa and the northern parts of South America on the other, suggests very forcibly that South America was at an See also:early date connected with Australia by a transpacific See also:bridge and with Africa by a more northern transatlantic See also:tract of See also:land . In conformity with their wide dispersal, scorpions have become adapted to diverse conditions of existence, some thriving in tropical forests, others on open plains, others in sandy deserts, and a few even at high altitudes where the ground is covered with See also:snow throughout the See also:winter . In the tropics they aestivate at times of drought; and in the See also:Alps they pass the See also:cold months of the See also:year in a state of See also:hibernation . (R . I . P.) SCORPION-See also:FLY, the popular name given to insects of the See also:family Panorpidae, deriving the name from the fact that in the typical genus, Panorpa, the last two or three segments of the See also:abdomen are narrow and can be flexed over the back like a scorpion's tail . The scorpion-flies are remarkable for the See also:elongation of the oral region of the See also:head into a prominent See also:beak . The larva is See also:grub-like, beset with spines and generally furnished with eight pairs of abdominal See also:pro-legs in addition to the legs on the See also:thorax, which are short . They live in the See also:soil or in rotten See also:wood and are carnivorous . The species of the genus Bittacus are superficially strikingly similar to the Tipulidae or " daddy-longlegs "; while those referred to, Berens, are anomalous in being apterous and like small grasshoppers . They have usually been included in the order See also:Neuroptera, but it is now generally considered that they should form a distinct order, which is termed Panorpata or Mecaptera . |
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