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QUA, 



Lat.) A deep blood-red variety of dode- 

 cahedral garnet. It consists of silica 40*0, 

 alumina 27'6, oxide of iron 16'0, mag- 

 nesia 1OO, lime 3*5, chromic acid 2'6, 

 oxide of manganese 0'3. It occurs in 

 small masses or grains. It is generally 

 transparent, with a splendent, vitreous, 

 conchoidal fracture. As a gem it is 

 highly prized. 



PYROPHO'RUS. (from TrDp, fire, and 0opoc, 

 bearing, Gr. pyrophore, Fr.) A sub- 

 stance which has the property of igniting 

 merely on exposure to the air. It is an 

 artificial production, and may be vari- 

 ously prepared. M. Gay Lussac formed 

 a pyrophorus of one part of lamp-black 

 and two parts of sulphate of potash. 



PYROPHY'SALITE. A variety of topaz. 



PYROSO'MA. (from TTVO, fire, and crwjua, 

 a body, Gr.) The pyrosomse unite in 

 great numbers, forming a large hollow 

 cylinder, open at one end and closed at 

 the other, which swims in the ocean by 

 the alternate contraction and dilatation 

 of the individual animals which compose 

 it. A pyrosoma may thus be compared to 

 a great number of stars of botrylli strung 

 together; the whole being moveable. 



From the phosphorescent character which 

 they possess they have obtained their 

 name. It is a floating polyp, differing 

 from the coral in being locomotive. Pe- 

 ron observed that when irritated its phos- 

 phorescence was augmented. 



PYROXE'NE. (from 7n~p, fire, and tVoc, 

 a stranger, Gr.) The name given by 

 Haiiy and Brongniart to augite. See 

 Auffite. 



PYROXE'NIC. Composed of pyroxene or 

 augite ; containing augite ; resembling 

 augite. 



PYROXE'NIC PORPHYRY. Augitic por- 

 phyry. 



PY'RULA. (from pyrum, a pear, Lat.) A 

 genus of marine univalves, belonging to 

 the family Canalifera. Recent pyrulse are 

 found at depths varying to nine fathoms, 

 in mud and sand. The pyrula is a some- 

 what pyriform univalve, swelling in the 

 upper part, with no variciform sutures, 

 caudated, canaliculated, spire short, 

 aperture wide, outer lip thin, and not 

 slit, columella smooth. Six species have 

 been found fossil by Lamarck. Pyrulse 

 are also found in the London clay, and in 

 the Bognor sandstone. 



Q 



QUA'DRANGLE. A square ; a surface with 



four right angles. 

 QUADRA'NGULAR. (quadrangularis, Lat. 



quadrangulaire, Fr.) Four cornered; 



square ; having four right angles. 

 QUA'DRATE. (quadratus, Lat.) Square ; 



having four equal and parallel sides. 

 QUADRICA'PSULAR. In botany, having 



four capsules to a flower. 

 QUADRIDE'NTATE. Four-toothed. 

 QUADRILO'BATE. (from quatuor, four, 



and lobus, a lobe, Lat.) A term applied 



in botany to a part having four lobes ; as 



a quadrilobate leaf. 

 QUADRILO'CULAR. (from quatuor, four, 



and loculus, a cell, Lat.) Four-celled ; 



having four cells. 

 QUADRIPHY'LLOUS. (from quatuor, four, 



Lat. and QvXXov, a leaf, Gr.) In botany, 



having four leaves ; four-leaved. 

 QUADRIPLI'CATED. (from quatuor, four, 



and plica, a fold, Lat.) A term in con- 



chology ; having four plaits or folds, 

 QUADRIVA'LVULAR. (from quatuor, four, 



and valva, a valve, Lat.) A term in 



botany ; having four valves. 

 QUADRU'MANA. (from quatuor, four, and 



manus, a hand, Lat.) The second order 



of Mammalia, including the monkeys, 



lemurs, and onistites. All the animals of 



this order have the toes of the hind feet 

 free and opposable to the others, and all 

 the toes are as long and flexible as the 

 fingers. The great character which dis- 

 tinguishes the members of this order is 

 the possessing a moveable thumb on their 

 lower extremities opposed to the fingers. 



QUADRU'M ANGUS. Having four hands; 

 four-handed. 



QUA'DRUPED. (quadrupes, Lat. quadru- 

 pede, Fr. quadrnpede. It.) An animal 

 that goes on four legs ; that has four legs 

 and feet. 



QUA-QUA-VE'RSAL. (quaqua, Lat. on 

 every side, and versus, inclined, Lat.) 

 Inclined towards every side ; facing all 

 ways. 



QUAQUAVE'RSAL DIP. A term applied to 

 the dip of a bed which is inclined, facing 

 all sides. 



QUA'RRY. (carriere, Fr. le lieu d'ou Von 

 tire de la pierre.) A place whence are 

 obtained stones for building and other 

 purposes 



QUARTZ, (quarz, Germ, quartz, Fr. mot 

 emprunte de VAllemand.) Silex in its 

 purest form. Quartz is a hydrate of sili- 

 con, or silex with some water of crystalli- 

 zation ; it is a compound of a metallic 

 basis, silicium, and oxygen. Quartz is 



