We shall treat of this subject in the present place with the diseases of texture as in the case of the arteries, and shall allow it to follow phlebitis, because on the one hand, hypertrophy of the venous coats is intimately allied to inflammation of the veins, and because, on the other, without a previous explanation of the mode in which an excessive formation of the lining membrane takes place within the vein, many points in the following pages would hardly be intelligible.

Hypertrophy of the whole venous wall especially consists, on the one hand, in an augmentation of the mass, and in a simultaneous sclerosis of the cellular coat of the vein, and, on the other hand, in a thickening of the lining membrane of the vessel; an augmentation in the bulk of the circular fibrous coat is generally less marked; it is caused by the persistent impediment to the blood-current, and by the accumulation of blood in the vein, while the increased bulk of the cellular coat is principally occasioned by chronic inflammation of the vein, which is commonly perceptibly dilated, and at the same time assumes, as we have already remarked, a sort of arterial habitus.

Thickening of the inner coat of the vein is the especial result of an irregular formation of new layers from the blood; it is an endogenous production. Its occurrence in the venous system is rare, as compared with its frequency in the arteries, nor do we meet with it in the same highly developed form; moreover, in the veins it never occurs as a general constitutional disease, but is merely deposited through local conditions, such as the impediment presented to the current of blood, and occasionally the entrance of arterial blood into the vein.

The form under which the deposition of new layers of the lining membrane appears in the vein, is principally a. The same as that in which it generally occurs in the arteries; it usually constitutes an opaque, white, smooth, and plane stratum, admitting of being cleft into more or less numerous lamellae; occasionally it forms a thickish, nodular, and uneven layer; and sometimes it presents a reticulated or areolar appearance. The vein never attains that considerable degree of thickness which is so frequently observed in the arteries. In reference to its metamorphoses, we very rarely observe an ossification; in veins which lie by ossifying arteries, and are fixed in a bed of inflamed cellular tissue, as, for instance, the femoral veins, we observe the process of ossification chiefly occurring in the wall of the vein nearest to the artery.

b. As a second form of these anomalies, and one which is altogether peculiar to the veins, we must notice the vein-stones (phlebolites), which have in general not been sufficiently regarded by writers on diseases of the veins. We believe that we have recognized their true nature, and that they deserve to be considered in the present place. They are concretions of a round, oval, or cylindrical form, commonly of the size of a hemp-seed, a pea, a bean, or even of a hazel-nut, and of a white or whitish-yellow color, which either lie free (as is most commonly the case) in the vein, or, if they are of more considerable size, become wedged and fixed in the vein, and entirely close it; or, finally, they adhere to, or actually coalesce with, the lining membrane of the vein, by means of a cylindrical or fusiform projecting coagulum, or through delicate membranous structures. Large phlebolites often lie in saccular pouches on the side of the vein. In some cases, this pouch, together with the phlebo-lite, separates from the vein, when it and the vein are closely compressed in a capsule, formed from the wall of the vessel. The vein then exhibits a more or less distinctly contracting cicatrix at the spot. When the lining and the circular fibrous coats of the capsule are gradually destroyed, the phlebolite finally lies in a capsule of cellular tissue, and this appearance may have given rise to the opinion that the phlebolite is originally developed in the cellular tissue outside the vein. Phlebolites are of very common occurrence, either separately or in small groups, more especially in the pelvic veins; that is to say, in the vessels of the bladder, vagina, uterus, and rectum of old persons; they also occasionally appear in other portions of the venous system, and even occur in young persons. They are also sometimes met with in the spleen, and in the form of sand-like concretions in the cellular spaces of certain teleangiectases (as for instance supplementary spleens).

A careful examination of phlebolites, and an attentive consideration of the circumstances under which they are formed, yield the following results:

On cutting through the phlebolite, we discover that it is of a concentrically stratified structure; that the innermost lamellae are usually of a whitish-yellow color, and the outer ones white, the former being compact and exhibiting a glass-like brittleness, whilst the latter are softer and of an earthy texture. The outermost layers are composed of soft membranes, are usually white and opaque, and exhibit at different points a gelatinous translucence. The membranous structures, by means of which phlebolites are sometimes attached to the inner wall of the vessel, are prolongations, or duplicatures of this wall, and, as it were, coatings of the peripheral layer investing the concretion. There is very commonly a roundish cavity, or, instead of it, an irregular fissure within the nucleus of the phlebolite, which is dry, and of a rusty brown, or dull yellow color. The surface of phlebolites, in some rare cases, exhibits the appearance of being gnawed at separate points to different depths; and these spots are occasionally invested with a faded yellow, fatty, soft mass. The chemical analysis of phlebolites shows that they consist of an animal substratum, with phosphate and carbonate of lime and some magnesia. (John, Gmelin, Lehmann, and Hasse).

The conditions giving rise to the formation of phlebolites are, as far as we know, a retarded flow of the blood in dilated veins; thus we observe them in the pelvic veins of aged persons, and in these and other veins in young persons, in consequence of an impediment to the circulation of the blood by the pressure of fibrous tumors of the uterus, enlarged ovaries, or prolapsus of the uterus in women, or of an enlarged prostate gland or distended bladder in men. We have seen a case where the subcutaneous veins on the abdomen had become varicose, in consequence of anastomosing with the umbilical vein, and of its remaining patent, and were so plugged up with phlebolites, that the skin felt as if it were full of shot.

We are of opinion that there is first a slight coagulation of blood in the vein, around which, there is deposited in concentric layers a structure analogous to the lining membrane of the vessel and the deposition in the arteries, and formed from the plasma of the blood. These strata generally become opaque, and ossify from the interior towards the circumference in much the same order as that in which they have been produced, or in some comparatively rare cases, they undergo the atheromatous process. The nucleus which is formed from the coagulum then shrivels, assumes a rusty brown or dull yellow color as it dries, and leaves a cavity in the centre of the phlebolite varying according to its previous volume; or it undergoes cretefaction, and cannot be recognized within its calcareous capsule.

The large coagula which occur together with phlebolites in varicose veins, cannot be regarded, at least when of the ordinary size, as the first step in the formation of phlebolites. They are observed in all varicose veins, including even those in which phlebolites are of rare occurrence; nor do they always present a concentrically stratified structure. It may, however, very probably be the residua of these strata, remaining after their general solution, which furnish the nucleus for a subsequent phlebolite.

The view which we have advanced in reference to the disease of the veins considered in the present section, makes it worthy of notice, that, in addition to the differences it presents when affecting the veins instead of the arteries, this disease of the veins is characterized by the extremely rare manifestation of the atheromatous process in either of the forms of deposition from venous blood; indeed, as far as we are aware, it never occurs in a deposit of the first form, notwithstanding its great frequency in the corresponding deposition from the arterial blood.