877 



FEAGILARIA. 



FRAXINELLA. 



878 



varieties of fracture into compact, fibrous, radiated, and foliated. 

 The compact may be splintery, even, conclioidal, uneven, earthy, or 

 hackly. The fibrous may be coarse or delicate, straight or curved, 

 parallel or diverging ; and the diverging again is either stellular, 

 scopiform, or promiscuous. The radiated fracture is broad or narrow, 

 straight or curved, diverging or promiscuous ; and streaked or smooth. 



FRAGILARIA. [DIATOMACEJ:.] 



FRANCOA'CE^E, Francoadi, a very small natural order of Exogens, 

 consisting of the genera Framcoa and Tetilla. They are South American 

 herbaceous plants, with lyrate radical leaves and a scapose inflorescence. 

 The sepals and petals are four ; the stamens four times as numerous 

 and hypogynous, half of them being rudimentary. The pistil consists 

 of four carpels adhering by their interior angles, with a sessile 

 4-lobed stigma. The seeds are numerous, and contain a minute embryo 

 lying in a mass of fleshy albumen. Great differences of opinion have 

 existed among botanists as to the affinities of this order. I)r. Limlley 

 that its nearest affinity is with Dioncea, which chiefly differs 

 in its unilocular fruit, anisomerous flowers, and the want of sterile 

 stamens. Its seeds are absolutely the same in all essential respects. 



A portion of the flower-stem of francoa louchifolia. 



1, the stamens and pistil ; 2, a transverse section of the ovary ; 3, a seed ; 



4, the nucleus of the seed taken from within the spongy testa ; 5, a longitudinal 



section of the nucleus showing the minute embryo. 



KKANCOLIN. [PEBDICID.E.] 



FRA'XKKXIA, a genus of Plants, the type of the natural order 

 Prankmiacea, and named in honour of John Frankenius, a professor 

 of botany at Upsal, and the first enumerator of the Swedish plants 

 in ' Speculum Botanicon.' It has a 5-cleft style, the lobes oblong, 

 with the stigmas within. Capsules 1 -celled, with three or four valves, 

 and many seeded. These plants are small and heath-like, with 

 prostrate stems; the flowers usually rise from the forks of the stem, 

 or are disposed in terminal corymbs. 



P. pulterulenta, the Powdery Sea-Heath, has its leaves opposite 

 in whorls, obovate, retuse, glabrous, and the under surface powdery, 

 with ciliated petioles ; a slender root, and axillary terminal flowers 

 of a pale red-colour. This plant grows in the sand by the sea-shore 

 in many parts of Europe and Asia ; it is occasionally found on the 

 coMt of Sussex in England, but is very rare. 



P. lent* has clustered, linear, glabrous leaves, with revolute margins, 

 ciliated at the base; prostrate downy stem, and terminal axillary 

 solitary flowers. It is a native of the muddy salt-marshes by the 

 sea-coast, in many parts of Europe and the Canary Isles. In England 

 it in found principally on the eastern coast, and flowers in the months 

 of July and August. The flowers are generally flesh-coloured, but 

 sometimes white, with yellow claws. 



Don enumerates 16 species of this geniw, besides those already 

 named as being found in Great Britain. Of those not British plants 

 the majority occur in Africa and Australia, and some are found 



n South America. F. hiepida grows on the rocks extending from the 

 island of Cyprus to Siberia. The hardy species of this beautiful 

 evergreen genus are well adapted to ornament rock-work, and may be 

 easily cultivated. They may be propagated by cuttings or by dividing 

 the roots, and may also be grown from seed under a hand-glass. 



(Don, Dichlamydeoui Plants ; Babington, Manual of British 

 Botany.} 



FRANKENIA'CE/E, Frankeniadt, a small natural order of Exogens, 

 allied to Violacece and Sauvayesiacece, with a procumbent habit, small 

 leaves, and very often minute flowers half hidden among the leaves. 

 They are all furnished with a tubular ribbed calyx, and that, together 

 with their having 5 petals, a definite number of hypogynous stamens, 

 and a 1-celled capsule bursting into valves, to whose edges the seeds 

 adhere, gives them a distinctly limited character. The species are 

 chiefly found in the south of Europe and north of Africa ; they how- 

 ever occur in various other parts of the world ; four species from 

 Australia ; two are natives of the Cape of Good Hope ; one of South 

 America ; and three of temperate Asia. Endlicher says they are 

 mucilaginous and slightly aromatic. The leaves of Beatsonia portu- 

 lacifolia are used in St. Helena as tea. Franl:enia paucijlora, 

 remarkable for the size of its flowers, is a very pretty greenhouse 

 shrub. 



A twig of Frankenia pulverulcnta, natural si/.c. 



1, a flower ; 2, the pistil and stamens ; 3, a transverse section of the ovary, 

 all magnified. 



FRANKINCENSE, a resinous substance, the produce of the Alies 

 excelta- (De Candolle), the Pinua allies (Linn.), Common Spruce-Fir, 

 from which it either exudes spontaneously or more abundantly from 

 incisions of the bark. When it first flows out it is liquid, but on 

 exposure to the air concretes, and is collected during autumn and 

 winter. It occurs in two states, in tears (Tims, or Olibanum sylvestre), 

 and in large irregular lumps or compressed cakes. When recent the 

 colour should be white, or only inclining to yellow, subdiaphanous, 

 soft, tenacious, and glutinous : by the action of time it becomes hard, 

 and even friable, the colour having deepened into an orange hue. By 

 the heat of the hand it softens, and by a higher temperature liquifies. 

 It possesses a turpentine-like odour and taste. It is insoluble in 

 water, but completely soluble in alcohol with the aid of heat. 



It consists of two kinds of resin mixed with oil of turpentine. By 

 melting it in water, and straining it through strong cloths, it is 

 deprived of much of its oil, when it is termed Pix ArMa, or Burgundy 

 Pitch. 



For the genuine Thus, or Frankincense of the ancients, see Bos- 

 WELLIA ; also OLIBANUM, as the substances distinguished by this name 

 (derived from the Arabic Looban) were of different kinds, and 

 procured probably from Africa and Arabia, as well as from India. 



FRANKLINITE, a Mineral which occurs in attached crystals, 

 granular, and massive. The primary form of the crystal is a cube ; 

 its colour is deep iron-black. Opaque. Lustre metallic. Specific 

 gravity 4'37 to 4'09. Hardness 6'0 to 6'5. Streak deep red-brown. 

 Cleavage parallel to the planes of the regulur octahedron, but very 

 indistinct. Fracture couuhoidal. Magnetic, but without polarity. 



The massive varieties are amorphous. Structure granular, compact. 

 This mineral is found at Franklin, New Jersey, North America. 



According to Berthier it consists of 



Peroxide of Iron 



Oxide of Zinc 



Red Oxide of Manganese 



17 

 16 



99 



FRATERCULA. [AuK.] 



FRAXINELLA, the common name of a Plant belonging to the 



filaments, having glandular tubercles at their apex, and roundish 



