I. WHITE FIBROUS °ROANS.- Organiza lion. This consists of a union of white or grayish fibres more or less distinct accord ing to the part in which they are examined ; thus they are very apparent in most of the ligaments, in the fascia, in the periosteum, and in many tendons, as in those of the obliquus abdominis externus, pectoralis major, &c. In other structures, on the contrary, as in the greater number of tendons, the fibres are so small and so closely united that they cannot be perceived but with difficulty, although they be come more evident on maceration. In most parts of the body they observe a parallel direc tion, whilst in other places they pass in an irre gular manner, so as to cross and interlace with each other, occasionally constituting, as in the instance of the dura mater and of the tendinous centre of the diaphragm, a very intricate net work of fibres.
The result of a careful examination proves that the remarkably firm arid resisting threads which constitute the basis of the various fibrous organs, are composed of condensed cellular tissue. In certain regions we may perceive the gradual transformation of the cellular tissue into a fibrous organ, as in the formation of the superficial fascia of the abdomen ; whilst by prolonged maceration the most dense tendon or ligament may be reduced into a pulpy cellu lar substance: this opinion is corroborated by lsenflamm, who conceives that this tissue is formed by cellular fibres impregnated with gluten and albumen ; and also by Bedard, who regards it as being composed of cellular texture very much condensed. We may therefore conclude that the ideas of Professor Chaussier, as to the existence of an elementary organic solid, called by him the albugineous fibre, and which is supposed to form the basis of all the ligamentous and tendinous parts of the body, are erroneous.
The individual fibres are surrounded by pro cesses of a more lax membrane, which pene trates between them, and which is rendered particularly apparent by maceration and in cer tain diseases. The differences that are observed in contrasting the various fibrous organs with each other, a ligament for example with a ten don, seem principally to result from the larger or smaller proportion of the interfibrous cellu lar substance and on the degree of its conden sation. This combination of the common cel
lular tissue with the ligamentous fibres allows the fibrous organs to yield in a very slight de gree when extended by the elasticity which is thus bestowed, and also slightly to contract on themselves on the removal of the extending force.
Bloodvcssels.—The proper fibrous tissue re ceives but a small quantity of blood, the arteries being minute in size, and principally carrying a colourless fluid. The great vascularity of the dura mater and periosteum is no exception to this remark, because the vessels of these membranes are not proper to them, but to the veins they cover.
Absorbents.—The ravages of disease in the neighbourhood of joints, involving the liga ments in ulceration ; the sloughing of tendons, the destruction of the periosteum by the pres sure of aneurism, of the tunica albuginea to scrofulous or malignant fungus of the testis, are abundant proofs of the existence of absor bent vessels.
Nerves.—According to Alonro, nervous fila ments may be traced to some of the fibrous organs ; and other anatomists, Cruveilhier for instance, speak of nerves being furnished to the joints; in general, however, none are to he seen ; but as sensibility becomes developed in disease, we must presume that communications do exist with the encephalon.
Chemical properties.— The principal sub stances that have been detected in the fibrous as in the cellular tissue consist of coagulated albumen and gelatine; a small quantity of mucus and saline matter has also been disco vered. The effects of desiccation are well known, tendons and ligaments becoming hard, transparent, yellowish, and fragile. This tissue resists maceration for a long time, but at length it is rendered soft and flocculent, so that the fibres can be separated and unravelled ; ulti mately it is converted into a pulpy and fila mentous cellular mass.