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the claw of the mandible. When the apparatus is not in use the claws are closed up against the parts between the rows of teeth; but when the jaws are opened to bite the claws are turned outward, so that their points can be made to penetrate anything that comes between the jaws. The ordinary function of the mandibles is the killing and crushing of insects, so that the soft parts can be eaten by the spider, and in this preparation they are substantially aided by the maxillæ. Spiders will sometimes chew an insect for hours, until it becomes a mere ball of skin, only swallowing such bits as may happen to be sucked in with the blood. Let alone and unmolested, they bite nothing except insects that are useful for food. But when attacked and cornered, all species open their jaws and bite if they can, their ability to do so depending upon their size and the strength of their jaws. Notwithstanding the large number of pimples and stings ascribed to spiders, undoubted cases of their biting the human skin are exceedingly rare, and the stories of death, insanity and lameness from spider-bites are probably all untrue. Many experiments have been made to test the effect of the bites of spiders on animals. Insects succumb most readily to their bites, some sooner than others, but birds, except when bitten by the larger Mygale, recover after the lapse of a few hours. The effect upon man, even when the bite is deep enough to draw blood, is like the pricks of a needle, attended by little or no inflammation or pain. Even in cases where death among insects and birds ensues it is claimed by the authorities, men as eminent as Blackwall, Moggridge and Dufour, that the secretion from spiders' jaws is not poisonous, but that the animals die, when bitten, from loss of blood and mechanical injury.

Such is the prejudice against the spider, that its presence, no matter where found, whether in the open field or in a corner of the house, is an inducement for its inveterate enemy, man, to sweep it to the ground or floor and crush its frail life out with one blow of the foot. Few know, or

care to know, it would seem, the good it does for man. He owes to it, in a large measure, the protection of his crops, and no little of the comfort he enjoys in life. Spiders are carnivorous creatures, and destroy vast number of insects, many of which are man's worst enemies. They merit, and deservingly, too, his kindness and protection for the benefits they confer.

Tarantulas have been supposed to produce epilepsy by their bites, which could only be relieved by music of certain kinds. Such stories, and they have been widely circulated and believed, are the veriest nonsense, for tarantula-bites produce no such effects nowadays. These spiders, which live in holes in sand, out of which they reach after passing insects, are no more savage in their habits than other spiders, for Dufour, a celebrated French naturalist, once kept one that soon learned to take flies from his fingers without manifesting the least disposition to bite. Different species quickly learn, when treated with kindness, to regard man as their friend. I have seen Agalena take food from the hand out of a pair of forceps, or water from a brush, and even to reach on tiptoe after it from the mouth of a bottle placed for her accommodation. Though naturally timid and shy, and prone to flee to her funnel on man's approach, yet she has been known to permit the most unexpected familiarities without fear or resentment. Many a female has taken from my hand the proffered fly, and submitted to the gentle caresses of my finger down the back and abdomen with the most pleasurable satisfaction. They have come at the sound of my voice, dancing upon their sheeted web like one gone mad, so perfectly carried away with delight. An interesting experience of last summer during a brief stay in the country seems apropos at this time. While sauntering carelessly along a forest-road I came unexpectedly upon a rustic bridge, with a railing on one side, which overspanned a small watercourse. Leaning for rest and support against the railing, soon my attention was arrested by a huge female spider,

which I recognized as Epeira domiciliorum. She was evidently in quest of something, as I was led to suspect from her seemingly thoughtful and deliberate movements. I watched her closely and criticisingly for a long while, and in one of her contemplative moods, when she stood perfectly motionless and fixed as it were to the railing, I reached out my finger rather impulsively and began stroking her along the abdomen, a familiarity which she did not resent, and which seemed to give her the most intense delight. When the caressing had ceased, she would turn round and confront her newly-made acquaintance, but the lifting of the finger was always the signal for her to assume an attitude of the most perfect quiescence. That she enjoyed these little attentions there cannot be a shadow of doubt, or actions are no use in the interpretation of feeling. Had they been painful, she would have sought relief in flight, or in the manifestation of an untoward disposition towards her unintentional persecutor.

BOOK-LOVERS.

L

IVING in chinks and crannies of ranges in our homes, and occasionally in bookcases and closets where glutinous and sugary matters abound, but which has probably not been met with elsewhere, is a strange but beautiful little creature which, as far as can be determined, goes through the brief round of its existence without a name to distinguish it from its fellows.

Few entomologists have given any special attention to its family relationships. The possession of certain bristle-like appendages which terminate the abdomen, and which are no doubt comparable with the abdominal legs of the Myriopods, or Thousand Legs, classes it with the Bristle-tails, or Lepismas. In general form, a likeness to the larva of Perla, a net-veined neuropterous insect, is manifest, or to the narrowbodied species of Blattariæ, or Cockroaches, when divested of wings.

Lepisma saccharina, of Europe, which is indistinguishable from our ordinary American form, is far from uncommon in old, damp houses. Its structure is less complicated than the heat-loving species to which I have alluded, and there are likewise differences of habits which show themselves to the close investigator of natural phenomena.

Not unlike the cockroaches, which our little denizen of the hearth somewhat vaguely resembles in form, it affects hot, dry localities, and is always astir at nights in quest of its fare, for it disdains the light of the day and the consequent publicity of its deeds of shame and plunder.

Many a housewife in the discharge of duty has unearthed, so to speak, the miscreant from its hidden retreat, and sought

by foot or hand to crush the life that dares obtrude its uncleanly presence in her larder, but the cunning, swiftfooted Lepisma darts off, like a streak of light, to some near-by crack or breach, where it manages to hide from threatening danger. The bodies of these nimble, silentmoving creatures being coated in a suit of shining mail, which the arrangement of the scales so very much resembles, they have a weird and ghostly look. This appearance, and the swiftness of their movement, which the eye can hardly trace, have led the vivid mind of man, in country town and village, to dub them "silver witches."

So fleet of foot are they, and so like a wave of blurred light they cross the vision, that it is vain to try to figure what they are in shape and look. In death they yield their all of earth to prying science. Their body's form is narrow, flattened; their legs in pairs of threes, each of six joints. consisting, the basal joints broad, flat, triangular, the tarsal large, in number two, and armed at end with pair of claws incurved. The three thoracic segments are very like in size, and eight abdominals, of similar length and width. So weak it seems the rather long abdomen is, that two pairs or six of bristles, simple, unjointed, and freely movable, serve as support, and also, as in other groups of insects, as organs locomotive.

The mode of antenna-insertion-and the same prevails in the entire family—is much like that of the Myriopods, the front of the head being flattened and concealing, as in the Centipedes, the base of the antennæ. Indeed, the head of any of the Bristle-tails, as seen from above, bears a general resemblance in some of its features to that of the Centipede and its allies, and so, in a less degree, does the head of the larvæ of certain beetles and neuropters. The eyes are compound, the individual facets constituting a sort of heap. The mouth-parts are readily compared with those of the larva of Perla, the rather large, stout mandibles being hid at their tips by the upper lip, which moves freely up and down

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