G L A 



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G L U 



GLA'UCONITE. Called also firestone. 

 The Glauconie crayeuse of the 

 French geologists. This comprises 

 the chalk-marl, without any inter- 

 mixture of green particles, as well 

 as the limestone, called in Sussex 

 malm-rock, and the sands and 

 arenaceous marls and limestones 

 full of green particles of sil- 

 icate of iron, and termed the 

 wpper green sand and firestone. 

 Mantell. 



GLAUCON'OME. A genus of fossil 

 corals. Under this name Goldfuss 

 has described five fossils, four of 

 which, according to De Blainville 

 and Milne Edwards, belong to the 

 genus Vincularia, previously estab- 

 lished by De France. The fifth 

 species, common at Dudley, pos- 

 sesses, however, characters essen- 

 tially different from those of Vin- 

 cularia, and even from those 

 assigned by Goldfuss. Instead of 

 the stem being impressed on all 

 sides with rows of cells, it has them 

 only over half the surface, the other 

 half being striated longitudinally. It 

 is probable, adds Sir R,. Murchison, 

 that the position of the fossil in 

 the matrix prevented that author 

 from detecting the true characters 

 of the coral. 



GLATJ'COTJS. (glaucus, Lat. azure, 



<y\ew:os, Gr.) 



1. Of a sea-green colour ; grey or 

 blue ; azure. 



2. In botany, applied to the leaves 

 or stems of plants, when covered 

 with a fine mealiness of a sea-green 

 colour. 



GLI'MMEB. (Germ.) The name given 

 by Werner to mica. 



GLO'BTJLUS. A genus of fossil univalve 

 shells, belonging to the family of 

 the NaticaB ; as their name implies, 

 they are remarkable for their 

 globose figure and minute spire. 

 Eight species have been procured 

 from the English tertiary forma- 

 tions, and three from the carboni- 

 ferouslimestone and shale. Lycett. 



GLOM'ERIS. (from glomero, Lat. to 

 gather into a round heap.) A 

 myriapod, resembling a wood-louse, 

 which, like the armadillo, when 

 alarmed, rolls itself up into a 

 spherical ball. 



GLOSSOPTE'BIA. The name proposed by 

 Brongniart for a genus of fossil 

 ferns, whose elongated leaves or 

 fronds are covered by fine arched 

 dichotomous, often anastomosing, 

 nervures. Specimens are met with 

 in the carboniferous and oolitic 

 strata. 



GLO'TTIS. (from ryA^-ira, Gr.) The 

 upper opening of the larynx, at the 

 root of the tongue. 



GLTJCI'NA. (from ry\vKv? } Gr. sweet.) 

 An earth obtainable from the eme- 

 rald, beryl, and euclase, of all 

 which it forms a constituent part. 

 Sir H. Davy discovered that glu- 

 cina consisted of three parts gluci- 

 num and one part oxygen. Glucina 

 is soluble in the liquid fixed 

 alkalies, in which respect it agrees 

 with alumina. It is insoluble in 

 ammonia, but soluble in carbonate 

 of ammonia. It combines with all 

 the acids, and forms with them 

 sweetish salts, from which circum- 

 stance it obtained its name. It 

 was first discovered by Vauquelin 

 in 1798. 



GLUCINE. (from 7X^5, sweet, Gr.) 

 An earth composed of oxygen 30, 

 and glucinum 70. "When pure it 

 is a white powder, soft and some- 

 what unctuous ; specific gravity 

 nearly 3. 



GLUCI'NTTM. The metal which is the 

 base of the earth glucina ; it has 

 not yet been obtained in a separate 

 state. 



GLUME. (gluma> Lat.) The husk of 

 corn ; the chaff ; the outer husk of 

 corn and grasses ; the calyx of corn 

 and grasses. In the grasses, and 

 plants resembling them, the floral 

 envelopes are not called calyx and 

 corolla, but bractese. The two 

 outer bracteae are termed glumes. 



