48 



AGATE AGAVE. 



an article of luxury for the table : some of the other 

 species form an important article of food to the Rus- 

 sian peasant ; others, however, and indeed by far the 

 greater number, are either poisonous or nauseous in the 

 extreme. Among the natives of Kamschatka, the A. 

 muscarlus is used as an intoxicating liquor, which pro- 

 duces strong convulsions in all the limbs of the person 

 drinking it, followed by that kind of raving which 

 attends a burning fever. The species that are found 

 useful to man as food will be more particularly treated 

 of under MUSHROOM. 



Among the species described by Fries we find 

 very few which are not indigenous to Europe; those 

 which are not so being either of Siberia and the 

 northern parts of Asia, or of North America: in all 

 the colder regions they are found in great abundance, 

 becoming more rare as we approach the equator. 



Linnaeus and other botanists, particularly Persoon 

 and Fries, have arranged this genus in numerous 

 sub-genera; Fries has made thirty-six of these, in 

 which he considers the leaves of the first importance; 

 the presence of the membrane which covers the 

 leaflets, and the colour of the seed on the contrary, 

 he considers of only secondary importance. 



AGATE. An ornamental stone, classed by mine- 

 ralogists amongst the earthy minerals. The northern 

 part of our island furnishes very beautiful examples 

 of the agate hence their name of Scotch pebbles. 



Moss Agate. 



The agate is said to have derived its name from 

 the Achates, a river in Sicily. Its chemical character 

 is principally marked by the large quantity of silica 

 which it contains. The same stone sometimes con- 

 tains parts of different degrees of translucency, and 

 of various shades of colour ; and the endless combi- 

 nations of these produce the beautiful and singular 

 figures for which, together with the high polish they 

 are capable of receiving, agates are prized as orna- 

 mental stones. Although occasionally found in other 

 rocks, they are most usually met with in that variety 

 of the trap rocks called A'mygdaloid or Mandelstein, 

 forming detached rounded nodules, not cemented to 

 the base or mass of the rock, but easily separable from 

 it, and having generally a thin layer of green earth 

 interposed, and a rough irregular exterior. In other 

 cases the agate runs in veins for a considerable distance. 



There are many varieties of the agate ; but one of 

 the most beautiful is the moss agate, in which jasper 

 of various colours, as brown, yellow, and red, appears, 

 as it were, floating in a basis of chalcedony. It ex- 

 actly resembles moss, and when its arborisations are 

 distinct, it has a very beautiful appearance. The 

 engraving above is copied from a specimen in the 

 collection of the British Museum. 



This stone is sometimes cut into snuff-boxes and 

 ring-stones : the larger masses are hollowed into 

 mortars, and sometimes cut into elegant vases. It 

 was much prized by the ancients, who have left us 



several fine works of art formed of this stone. In the 

 royal cabinet at Dresden, there are some beautiful 

 vases of agate. At Oberstein on the Rhine, the 

 amygdaloid rocks are regularly quarried for the agates 

 they contain, and these are cut and polished, and 

 exported to other countries. The manufacture of the 

 agates of this country, is carried on to a very consi- 

 derable extent. See JASPER. 



AGATHOSMA (Willdenow). A genus of above 

 twenty species, natives of the Cape of Good Hope. 

 They are all evergreen shrubs, suitable for the green- 

 house. Linnaean class and order, Pcntandria Mono- 

 gynia. Natural order, Rutacece, The inhabitants of 

 Southern Africa use the leaves of A. pulchella dried 

 and powdered, under the name of Buckee, to mix 

 with the grease with which they smear their bodies ; 

 to give, in their opinion, an agreeable perfume, though 

 to strangers it is a most offensive scent. 



AGAVE (Linnaeus). Commonly called the 

 American aloe. A genus of remarkable succulent 



Agave Americana. 



plants, containing eleven species. Linnaean class and 

 order, Hexandria Monogynia. Natural order, Bro- 

 melMcecE. Generic character : calyx, coloured, peta- 

 loid, tubular and funnel-shaped, in six equal divisions, 

 united at the base to the ovary, which is inferior. 

 Stamens six, inserted in the calyx. Fruit, a longish 

 three-sided capsule, of three places filled with two 

 ranks of seeds. The most remarkable, and perhaps 

 the most generally useful species of this family is A. 

 Americana. The plant propagates itself by seeds, 

 and by a few suckers or offsets. The principal divi- 

 sion of the plant extends itself slowly ; requiring a 

 period of from seven to ten years before producing 

 a terminal flowers. When these do come forth, they 

 present a most interesting spectacle ; the stem rises 

 thirty feet high, bearing hundreds of greenish-white 

 flowers on an elegant branched spike. When the 

 seeds are ripe, the whole division of the plan* pro- 

 ducing them dies. 



