The external appearances, however, yield no information as to the condition of the parts within, or the nature of this newly-formed struc ture; and on this subject anatomical investiga tion affords but little satisfactory knowledge. When a nwvus is extirpated, it seems to consist of a mass of cellular tissue, collapsed and flaccid, which cannot be unravelled, and seems to bear no proportion in size to that of the tumour before removal. If it be cut away close to its defined edge, and without the ex tirpation of the zone of small vessels already described, the bleeding is frightful, and in very young children may be fatal, evidently sheaving that these vessels are not endowed with con tractility, and are a diseased and a new forma tion. If a nmvus is injected, it only affords a swollen and unshapely mass of whatever ma terial had been used, and throws no light what ever on the real pathology of the disease. Here, then, in the absence of demonstration, theory and conjecture are permitted, and all that is known, or supposed to be known, is only the fruit of speculation.
Bell supposed the tumour to consist of a congeries of cells, into each of which an artery and vein opened; that these cells increased both in number and in size with the growth of the patient, until they became immense reser voirs of blood ; and, finally, that they became so distended as to burst and destroy life, as any other aneurism would, by a profuse discharge of blood. But still this explanation is defec
tive, as showing nothing of the nature of the cells themselves, or why blood poured out into them should not coagulate as it would in any other cellular structure. It remained for Du puytren to offer an ingenious and extremely probable hypothesis relative to these points, and he conceived the aneurism by anastomosis to be a " tissu erectile," analogous to that naturally found in many parts of the body.* In the penis of man, and in the clitoris and mamella of woman, there is a particular structure, capable of receiving, retaining in a fluid state, and afterwards returning a given quantity of blood. These organs are provided with strong fibrous sheaths, that prevent their distension beyond a certain size, and are fur nished with a number of nerves that preside over the circulation through them, and deter mine their conditions of erection and col lapse. The abnormal " tissu erectile" consists of a cellulated structure, in itself of the same or a similar structure, but not being invested by a fibrous sheath or capsule, its growth is unrestrained, and the size to which it may attain has no limit ; and as it has not a similar distribution of nerves, there is nothing to occa sion either unwonted distension or collapse, and it is left solely under the influence of those causes that act upon the circulation. (See