ARALIA, berry-bcaring angelica, in bo tany, a genus of the Pentandria Pentagy. nia class of plants, the flowers of which are collected into an umbel, of a globose figure, with a very small involucrum ; the perianthium is very small, divided into five parts, ancl placcil on the germen ; the corolla consists of five, ovato-acute, ses sile, reflex petals, the fruit is a roundish, coronated, striated berry; having five cells : the seeds are single, hard, and ob. long. There are four divisions, viz. A. leaves entire ; B. leaves lobed ; C. leaves in finger-like divisions ; Dleaves decom pound, and more than decompound. In the first there are three species ; in the second one ; in the third two ; and in the fourth four.
..kRANEA, in natural history, the spider, a genus of insects of the order Aptera. Cen. char. legs eight ; eyes eight, some times six ; mouth furnished with two hooks, or holders ; feelers two, jointed, the tips of which in the male distinguish the sex; abdomen terminated by papillx, or teats, through which the insect draws the thread.
One of the largest of the European spi ders is the Arctnea diadema of I..innxus, which is extremely common in England, and. is chiefly seen during the autumnal season in gardens, &c. The body of this species, when full grown, is not much in ferior in size to a small hazel nut : the abdomen is beautifully marked by a lon gitudinal series of round, or drop-shaped milk-white spots, crossed by others of similar appearance so as to represent, in some degree, the pattern of a small dia dem. This spider, in the months of Sep tember and October, forms, in some con venient spot or shelter, a large, round, close, or thick web ofyellow silk, in which it deposits its eggs, guarding the round web with a secondary one of a looser tex ture. The young are hatched in the en suing May, the parent insects dying to wards the close of autumn. The Aranea diadema, being one of the largest of the common spiders,serves to exemplify some of the principal characters of the genus in a clearer manner than most others. At the tip of the abdomen are placed five papillx or tents, through which the insect draws its thread; and as each of these papillz is furnished with a vast number of foramina or outlets, disposed over its whole surface, it follows, that what we commonly term a spider's thread, is in reality formed of a collection of a great many distinct ones, the animal possessing the power of drawing out more or fewer at pleasure ; and if it should draw from all the foramina at once, the thread might consist of many hundred distinct filaments. The eyes, which are situated on the upper part or front of the thorax, are eight in number, placed at a small distance from each other, and having the appearance of the stemmata in the generality of insects. The fangs, or piercers, with which the animal wounds its prey, are strong, curv ed, and each furnished on the inside, near the tip, with a small ob long hole or slit, through which is eva cuated a poisonous fluid into the wound made by the point itself, these organs ope rating in miniature on the same princi ple with the fangs in poisonous serpents. The feet are of a highly curious structure ; the two claws with which each is ter minated being furnished on its under side with several parallel processes,resembling the teeth of a comb, and enabling the ani mal to dispose and manage with the ut most facility the disposition of the threads in its web, &c.
Aranea tarantula, or Tarantula spider, of which so many idle recitals have been detailed in the works of the learned, and which, even to this day, continues in some countries to exercise the faith and igno rance of the vulgar, is a native of the warmer parts of Italy, and other warm European regions, and is generally found in dry and sunny plains. It is the largest
of all the European spiders, but the ex traordinary symptoms supposed to ensue from the bite of this insect, as well as their supposed cure by the power of mu sic alone, are entirely fabulous, and are now sufficiently exploded among all ra tional philosophers. The gigantic Aranea avicularia, or Bird-catching spider, is not uncommon in many parts of the East In dies and South America, where it resides among trees, frequently seizing on small birds, which it destroys by wounding with its fangs, and afterwards sucking their blood. miring the early part of the last century, a project was entertained by a French gentleman, Monsieur Bon, of Montpelier, of instituting a manufacture of spiders' silk, and the royal Academy, to which the scheme was proposed, ap pointed the ingenious Reaumur to repeat the experiments of Monsieur Bon, in or der to ascertain how far the proposed plan might be carried; but, after making the proper trials, Mr. Reaumur found it to be impracticable, on account of the natural disposition of these animals, which is such as will by no means admit of their living peaceably together in large num bers. Mr. Reaumur also computed that 663,522 spiders would scarcely furnish a single pound of silk. Monsieur Bon, how ever, the first projector, carried his expe riments so far as to obtain two or three pair of stockings and gloves of this silk ; which were of an elegant grey colour, and were presented as samples, to the Royal Academy. It must be observed, that in this manufacture it is the silk of the egg bags alone that can be used, being far stronger than that of the webs. Monsieur Bon collected twelve or thirteen ounces of these, and having caused them to be well cleared of dust, by properly beating with sticks, he washed them perfectly clean in warm water. After this they were laid to steep, in a large vessel, with soap, saltpetre, and gum arabic. The whole was left to boil over a gentle fire for three hours, and were afterwards again washed to get out the Soap ; then laid to dry for some days, after which they were carded, but with much smaller cards than ordinary. The silk • is easily spun into a fine and strong thread : the difficulty being only to collect the silk bags in sufficient quantity. There re mains one more particularity in the histo ry of spiders, viz. the power of flight. It is principally in the autumnal season that these diminutive adventurers ascend the air, and contribute to fill it with that infi nity of floating cobwebs which are so pe culiarly conspicuous at that period of the year, When inclined to make these aerial excursions,the spider ascends some slight eminence, as the top of a wall, or the branch of a tree ; and turning itself uith its head towards the wind, ejaculates several threads, and rising. from its sta tion, commits itself to the gale, and iv thus carried far beyond the height of the loftiest towers, and enjoys the pleasure of a clearer atmosphere. During their flight it is probable that spiders employ themselves in catching suchminute wing edinsects as may happen to occur in their progress ; and when satisfied with their journey and their prey, they suffer them selves to fall, by contracting their limbs, and gradually disengaging themselves from the thread. which supports them. See Plate I. Entomology, fig. 7 and 8,