FIBROINE. 



[ 263 ] FILAMENTOUS STRUCTURES. 



rily determined. A substance resembling 

 fibrine in many of its characters, if not iden- 

 tical with it, occurs upon the siu-faces of in- 

 flamed membrane, &c. ; in these cases it 

 generally includes the other elements of in- 

 flammation, and almost always a number of 

 minute granules of fat. 



Fibrine is coloured by the test-liquids of 

 Millon and Pettenkofer. 



The fibrinous plasma of the lower animals 

 resembles fibrine in many respects, but does 

 not separate in fibres. 



See Blood, p. 83. 



BiBL. That of Chemistry, animal. 



FIBROINE.— The principal constituent 

 of silk, cobwebs, and the horny skeleton of 

 sponges. In the pure state, it is white, in- 

 soluble in water, alcohol, aether, acetic acid, 

 and ammonia. It is amorphous. 



BiBL. That of Chemistry, animal. 



FIBRO-PLASTIC TISSUE. See Tis- 

 sue, FIBRO-PLASTIC. 



FIBROUS and FIBRO - VASCULAR 

 BUNDLES. See Tissues, vegetable. 

 FIBROUS STRUCTURES, of Plants. 



— This term is somewhat equivocal, and re- 

 quires a little explanation here. In common 

 language all vegetable substances are termed 

 fibrous which can be separated into more or 

 less fine threads possessing a certain degree 

 of tenacity ; special examples are furnished 

 by those forming the materials for textile 

 fabrics. But the anatomical or microscopical 

 structures comprehended here are exceedingly 

 varied, including not only hber-fibres, but 

 spiral vessels, and even hairs. Thus while 

 Flax (PL 21. fig. 2) is the liber of Linum 

 usitatissimum, Hemp (PI. 21. fig. 6) oi Can- 

 nabis, Jute (PI. 21. fig. 3) of Cor chorus 

 capsularis, &c., Puya (PI. 21. fig. 26) of 

 Boehmeria Puya, and the material of Chinese 

 grass cloth (PI. 21 . fig. 25) of Boehmeria 

 nivea, Coir (PI. 21. fig. 4), the liber-like 

 fibre of the husk of the cocoa-nut, — the 

 Manilla hemp (PI. 21. fig. 7) is composed of 

 the fibro-vascular bundles of Musa textilis, 

 and Cotton (PI. 21. fig. 1) consists of the 

 hairs covering the seeds of species of Gossy- 

 pium. These and similar substances may be 

 conveniently referred to the article Textile 

 substances, but they are also spoken of 

 under Liber, Hairs, and under their re- 

 spective heads. 



In botanical language, the word fibre has 

 come into use in two very dififerent senses. 

 First, any long cell attenuated to a point at 

 both ends, and with its walls thickened with 

 ligneous secondary deposits, is called njibre 



by some authors. Thus the term woody 

 fibre is applied to the shorter cells of this 

 kind which make up the substance of most 

 solid woods, while the term liber-fibre is ap- 

 plied (with more justice) to the often ex- 

 tremely elongated wood-tubes which form 

 the elements of the liber of Dicotyledons 

 and the woody part of the fibro-vascular 

 bundles of the Monocotyledons. (See Tis- 

 sues, vegetable.) The characters of 

 structures of this kind will be given under 

 Liber and Wood. Secondlv, the term 

 fibre is applied to the secondary deposits 

 upon the walls of cells, vessels, ducts, &c., 

 which, instead of forming continuous pitted 

 layers, take the pattern of spiral or analogous 

 lines, and, by increasing in consistence, sub- 

 sequently form real fibres, often elastically 

 unrollable, of firmer substance than the 

 cell-wall upon w'hich they were originally 

 deposited. The numerous modifications of 

 these fibrous deposits upon the walls of cells 

 are spoken of under the heads of Spiral 

 Structures, Vessels, and Secondary 



DEPOSITS. 



It must not be omitted here that the walls 

 of many cells and liber-fibres, which appear 

 at first sight to be composedof homogeneous 

 laminae, may often be made to exhibit spu-al 

 streaks, by the use of reagents and macera- 

 tion j indeed, they present themselves during 

 the natural dissolution of the membranes of 

 some of the Oscillatoriacese (Ainactis, Schi- 

 zosiPHON (PI. 4. figs. 13, 15). Hence some 

 authors have recently recurred to the old 

 notion that all vegetable membranes are 

 formed of fibres cemented or blended toge- 

 ther. This is again strongly combated by 

 others, as regards the primary membrane of 

 cells. We enter more particularly into the 

 details under the article Spiral Struc- 

 tures of Plants. 



FICUS, Linn. (Figs). — A large genus of 

 Urticaceae (Dicotyledons), some of which 

 possess remarkably thick epidermis and cu- 

 rious pseudo-glandular structm-es connected 

 with it. Ficus elastica, one of the plants 

 yielding india-rubber, now^ commonly grown 

 in pots in rooms, is a good example. The 

 clavate bodies (PI. 39. fig. 27) of Meyen, de- 

 veloped in cavities in the leaf, beneath the 

 epidermis, contain crystalline deposits. (See 

 Glands and Raphides.) 



FILAMENTOUS STRUCTURES, of 

 Plants. — This name would be more appli- 

 cable than fibrous structures to such sub- 

 stances as Cotton, which consists of elon- 

 gated hairs (PI. 21. fig. 1), and indeed to all 



