Patches, more or less extensive, and having the outward appearance of cartilage, are of common occurrence in fibrohs tumours. The period at which this change occurs is inde terminate; nor has the size of the growth any appreciable influence upon it. We have examined some specimens of this kind with out detecting any cartilage corpuscles, and incline to regard the outward change as simply signifying an increase of density and closeness of' deposition of fibres.
Nor is the alleged " ossification " of these tumours, according to our observation, more real. We have not succeeded in detecting in the ossified-looking parts either the cor puscle or the laminated structure of bone, but simply saline particles or granules closely or loosely set in the organic basis of the tumour : actual ossification has, however, sometimes been seen. This saline precipitation commences indifferently in any part of the mass, and commonly shows itself in several points simultaneously, these being usually seated near the centre ; it is far from unusual, however, to find most accumulation at the peri phery, and not a few cases have been mentioned by Meckel, Louis, ancl others, in la hich the central parts, still fibrous, have been found encased in an earthy shell of variable thick ness. The density of the calcareous matter (grey or yellowish in colour) varies greatly. lf it be most common to find this substance friable and porous, in other cases, the saline substance is extremely hard and dense, resem bling marble of eburnated bone. From Pro fessor Daniell's analysis of a large tumour, de scribed by Mr. Arnett (Med. Chir. Trans. xxiii. p. 202), we may infer the great extent to which the animal constituents may be re placed by inorganic salts, as also the nature of these : here w ere found, animal matter, including water and ammoniacal salts, 35 ; phosphate of lime, with a small quantity of phosphate of magnesia, 56 ; carbonate of lime, 5 ; alkaline sulphates, phosphates, and xnuriates, 4=100. The extent of the growth converted into calcareous matter varies great ly. Bayle refers to a tumour larger than a new-born infant's head, containing ten points of " ossification,"— the laroer scarcely the size of a pea, the smaller notbbigger than a grain of wheat : Mr. Arnott's case exemplifies the opposite extreme of almost total conversion into saline substance. When either converted altogether into earthy matter, or provided with an earthy crust of' variable thickness, these bodies have been described as " calculi."
Occurring most frequently in the uterus, these concretions of fibrous origin have also been observed in the cranium by Cruveilhier (Rev. Med. Sept. 1833), by Krull and others.
We have seen one as large as a walnut, which had been connected with the integuments of the face, in the possession of Mr. Liston.
The period at which calcareous deposition commences is altogether accidental. The size of growths has no influence upon it : the largest tumour we ever met with con tained not a single earthy particle, visible with the naked eye; while it is common to find very small growths partially calcareous, and small and large tumours in the same uterus may present this change to an equal amount. It has even been maintained by Sebastian, that ossiform deposit is more common in small than large tumours ; but although this idea may be rendered probable d priori by the con sideration that the occurrence of this change would prevent further enlargement of the pro per fibrous structure, yet we doubt strongly its being supported by facts. With the pro gress of saline precipitation (obviously so when the earthy changes occur on the peripherie surface, less distinctly and rapidly, though not less really, when they arise in the central parts) the connection of these growths with sur rounding tissues, becomes less and less inti mate ; the vessels undergo obliteration, and a few filamentous shreds may alone keep up the union, until eventually the calcareous mass ceases to have structural connection with the organs. This condition is in some cases the prelude to its expulsion from the body. The saline matter sometimes appears to act as an irritant on the adjoining fibrous structure, and induce local exudation, suppurative or other wise ; probably this is the state referred to by Bayle, as "caries" of the alleged osseous struc ture of a fibroma.
Fibrous tumours of the reddish variety, soft, vascular, and of loose texture, are subject to internal congestion, which when these growths are situated in certain situations, as for example, under the mucous membrane of the uterus, may, aided by expulsive efforts of that organ, lead to rupture of the superficial layers of the growth, and terminate in external hmmorrha.e. According to Madame Boivin, such tumours may be regarded to a certain extent as of erectile nature, inasmuch as they admit of becoming hard and tumid with blood at certain periods, especially the eatamenial.