JUN 



JUP 



juli roll lliemselves up into a flat spiral; 

 their general motion is rather slow and 

 undulatory. 



JUNCUS, in botany, rush, a genus of 

 theHexandria Monogynia class and order. 

 Natural order of Tripetaloidex. Junci, 

 Jussieu. Essential character : calyx six- 

 leaved ; corolla none ; capsule one-celled. 

 There are twenty-nine species. The 

 rushes have a simple grassy stem, with- 

 out leaves or knots, or else knotty, with 

 a sheathing leaf at each knot ; flowers 

 terminating or lateral, corymbed or pani- 

 clcd, with the branchlets spathaceous at 

 the base. 



These plants agree with the grasses in 

 the glumes of their flowers, and the 

 sheaths of their leaves ; they differ in 

 having the stems filled with pith, whereas 

 in grasses it is hollow. The rushes form 

 an intermediate link between the grasses 

 and some of the liliaceous plants, as an- 

 thericum, &c. 



They form naturally two divisions, one 

 without leaves allied to scirpus, &c. and 

 the other with leafy stems. But all clas- 

 sical botanical writers, says Dr. Smith, 

 have judiciously preserved this very na- 

 tural genus entire, notwithstanding the 

 capsule is in some species one celled, 

 in others three celled. The sea rushes 

 are planted on the sea-banks in Hol- 

 land ; the roots running deep into the 

 sand, and matting very much, so as to 

 hokl it together. In the summer, when 

 they are full grown, they cut them, and 

 when dry, work them into baskets. 



JUNGERMANNIA, in botany, so nam- 

 ed from Louis Jungermannus of Leipsic, 

 Professor of Botany at Atorffi a genus of 

 the Cryptogamia Algae, Linnseus, class 

 and order. Natural order of Hepaticae, 

 Jussieu. Thirty species of these mosses 

 are arranged in five subdivisions, in the 

 fourteenth edition of " Systema Vegeta- 

 bilUim." Dr. Withering has forty-eight 

 species in the third edition of his *' Ar- 

 rangement of British Plants ;" he says 

 many of them are beautiful microscopic 

 objects. 



JUNGIA, in botany, so named from 

 Joachim Jungius, M. D. a genus of the 

 Syngenesia Polygamia Segregata class 

 and order. Natural order of Composite 

 Oppositifolize. Cinarocephalse, Jussieu. 

 Essential character: calyx common, 

 three flowered; receptacle chaffy ; flo- 

 ^ rets tubular, two-lipped ; outer lip ligu- 

 ' late ; inner two-parted. There is but 

 one species, viz. J. ferruginea, the stems 

 of which are woody, covered with a fer- 

 ruginous down ; leaves alternate, five- 

 lobed, cordate at the base ; lobes rounded, 

 blunt ; they are hirsute, and underneath 



hoary; panicle terminating, large, de- 

 compounded ; heads of flowers small, 

 heaped. It is a native of South America. 



JUN1PERUS, in botany, juniper-tree, a 

 genus of the Dioecia Monadelphia class 

 and order. Natural order of Conifers. Es- 

 sential character ; male, calyx of the ament 

 a scale ; corolla none ; stamina three : fe- 

 male, calyx three-parted ; petals three ; 

 styles three ; berry three-seeded, irregu- 

 lar with the three tubercles of the calyx. 

 There are twelve species ; some of these 

 are lofty handsome trees; but the J. com- 

 munis, common juniper, is a low shrub, 

 seldom more than three feet in height, 

 sending out many spreading tough bran- 

 ches, inclining on every side, covered with 

 a brown or reddish bark, with a tinge of 

 purple. The male flowers are sometimes 

 on the same plant with the females, but at 

 a distance from them ; they are commonly 

 on distinct plants. The female flowers are 

 succeeded by roundish berries, which are 

 at first green, and when ripe are of a dark 

 purple colour. They continue on the 

 bush two years, and are sessile in the axil 

 of the leaves. Juniper is common in all 

 the northern parts of Europe, in fertile or 

 barren soils, on hills or in valleys, in open 

 sandy plains, or in moist and close woods. 

 In England it is found chiefly on open 

 downs, in a chalky or sandy soil. 



IVORY, a hard, solid, and firm sub- 

 stance, of a white colour, and capable of 

 a very good polish. It is the tusk of the 

 elephant, and is hollow from the base to 

 a certain height. It is brought to us from 

 the East Indies, and from the coast of 

 Guinea. Tusks are valuable in proportion, 

 to their size ; and it is observed, that the 

 Ceylon ivory, and that from the island of 

 Achem, do not become yellow by wear, 

 as all other ivory does : hence the teeth of 

 these places bear a larger price than those 

 of the coast of Guinea, 



IVORY black, is prepared from ivory, or 

 bones burnt in a close vessel. This, 

 when finely ground, forms a more beauti- 

 ful and deeper colour than lamp-black ; 

 but, in the common methods of manufac- 

 turing, it is apt to be adulterated with 

 charcoal dust, so as to be almost, or alto- 

 gether, unfit for use. 



JUPITER, }/ , in astronomy, one of the 

 superior planets, remarkable for its great 

 brightness. See ASTRONOMY. 



Jupiter is the brightest of all the planets, 

 except Venus. He moves from west to 

 east in a period of 4332 days, exhibiting 

 irregularities similar to those of Mars. 

 Before he comes into opposition, and when 

 distant from the sun about 115, his mo- 

 tion becomes retrograde, and increases in 



