Page:The American Cyclopædia (1879) Volume XV.djvu/275

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SPHINX tures can with difficulty be traced. The head had been covered with a cap, the lower part of which remains, and it had originally a beard, the fragments of which were found below. SPIDER 263 The Great Sphinx. [mmediately under the breast stood a granite ")let, and another of limestone on either side resting against the paws. The first contains a representation of Thothmes IV. offering in- cense and making libation to the sphinx, with a long inscription in hieroglyphics reciting the titles of the king. On the paws are inscrip- tions of the Roman times, expressive of adora- tion to the sphinx or to the Egyptian deities. SPHINX, one of the names of the Guinea baboon (cynocephalus papio, Desm.). It is irely seen in menageries, though it is remark- ibly intelligent ; it is probably one of the spe- ies represented on the Egyptian monuments. [t was known to Pliny. (See BABOON.) SPHINX CATERPILLAR. See HAWK MOTH. SPH1GMOGRAPH. See PULSE. SPICE ISLANDS. See MOLUCCAS. SPICEWOOD. See FEVER BUSH. SPIDER, a division of the insect order arach- nida, which also includes the mites and scor- pions. The general character of the order, which seems intermediate between crustaceans and insects proper, though nearest to the lat- ter in mode of development, are given in the article AEACHNIDA. The external envelope is usually soft and tough, but not corneous, and is provided with papillae, spines, bristles, and hairs, giving a furry or velvety, but generally disgusting aspect ; the inner membrane of the skin is thin and colorless, and under it is a layer of colored vesicles and granules, the seat of the brilliant hues observed in many species. The body is divided into thorax and abdomen, the head is continuous with the chest, and there are no wings. From the inner surface of the cephalothorax are given off various pro- cesses serving for muscular insertions, forming at the bottom a solid horizontal plate, a kind of internal skeleton attached to the sternal plates by ligaments. The muscles are dirty yellow, transversely striated, and in general disposition like those of crustaceans ; the prin- cipal masses are found in the cephalothorax, acting on the mouth, tactile organs, and legs ; in those with an unarticulated abdomen there are numerous interlacing fibres encompassing this part, and sending processes among the organs and to the ventral tendinous ligament. The locomotive organs on the cephalothorax are four pairs of legs, of which the first in some resembles a posterior pair of metamor- phosed jaws; each foot usually ends in two claws, but some have only one, and others three or four; each leg has usually seven joints ; in some the tarsi have a great number of joints, which can be readily dropped off for the pur- pose of escape, and are reproduced at the time of the moult. The central part of the ner- vous system is situated around the oesophagus, sending nerves to the head and limbs; the splanchnic nerves for the viscera are well de- veloped. The antennae are transformed into the prehensile and masticatory mandibles; a delicate sense of touch resides in the palpi, and in the end of the feet, which are employed in constructing the web ; the senses of taste, smell, and hearing have not been satisfactorily localized in any special organs. The eyes are smooth and simple stemmata, variously placed on the cephalothorax according to the mode of life of the species, usually eight, sometimes six, of different sizes, grouped symmetrically on the anterior median line or scattered on its lateral border, and directed accordingly up- ward or laterally ; the diurnal species have the pigment greenish, reddish, or dark, and the nocturnal splendidly lustrous, as in the cats. The cheliceres or fangs have the form of bi- articulated antennae, the basal joint being very thick, and the terminal one a very sharp hook folded under the former when not in use, but capable of erection for defence or seizing prey, and having at the apex the opening of the duct of a poison gland ; the first pair of maxillae are changed into very long, tactile or prehensile organs, the upwardly directed prom- inences of whose basal joints cover the en- trance of the mouth, and serve as bruising organs ; there is also a tumid hairy upper lip ; the borders of the oral cavity may be approx- imated so as- to form a suctorial canal, as well as the very short and horny oesophagus. The stomach is in the cephalothorax, and is divi- ded behind the sucking apparatus into lateral halves extending in an arched manner in front, where they become contiguous or united into a ring, from which are given off four or five pairs of caeca directed toward the insertion of