It is evident that for any case resembling mine in its essential features the name of Molluscum Fibrosum is more appropriate than that of Fibroma Molluscum, used by Virchow and other German writers.

DESCRIPTION OF PLATE VI.

FIG. 1.-Portion of the skin of the back affected with molluscum fibrosum: the under surface dissected so as to expose the tumours lying at different depths in the substance of the skin. Natural size.

FIG. 2.-Microscopic appearance of one of the smallest tumours of molluscum; the entire tumour being simply flattened between two plates of glass. The accompanying scale represents hundredths of an inch.

Fig. 2

ON

CERTAIN MORBID CHANGES IN THE

NERVOUS SYSTEM

ASSOCIATED WITH

DIABETES.

BY

W. HOWSHIP DICKINSON, M.D. CANTAB., F.R.C.P.,

PHYSICIAN TO THE HOSPITAL FOR SICK CHILDREN; ASSISTANT-PHYSICIAN TO ST. GEORGE'S HOSPITAL.

Received Jan. 11th.-Read Feb. 8th, 1870.

DIABETES has hitherto been regarded as a functional disorder, and has been attributed to erroneous action rather than structural change. This view, however, must be looked upon as only provisional. Function is simply the expression of structure. Structure and function are inseparable as cause and effect. A temporary disturbance of function has its source in a transient alteration in the solids or fluids of the body. Where, as in diabetes, function is permanently altered, there must needs coexist equally abiding change in the mechanism of the organs concerned. In this belief, relying upon our improved means of research, I have, as opportunity offered, inquired into the state of the more important organs in diabetic subjects. Using the method of Dr. Lockhart Clarke, it was at once seen that the nervous system was the seat of important alterations, an observation which gained

significance from the discovery of Bernard that puncture of a certain part of the medulla oblongata rendered the urine saccharine. I have therefore had special regard to the condition of the nervous centres, though I have not neglected to examine the lungs, liver, stomach, spleen, and kidneys.

Since the discovery of Bernard attention has been directed to the state of the medulla in persons who have died of diabetes, and cases have been recorded in which softening and other morbid changes have been here found. The lesions, however, have been various in kind, and little pathological importance has been generally attached to them.

M. Abeille1 quotes from M. Luys two instances of diabetes in which there was softening, discoloration, and injection of the medulla, which lesions he regards as consecutive upon the malady, not as antecedent to it. Dr. Lockhart Clarke2 described a softened medulla from an epileptic patient who was also the subject of diabetes, and other instances might be given in which disease in this neighbourhood has been found to accompany a saccharine state of the urine.3

The changes which have been alluded to, however, have been found with such comparative infrequency in connection with diabetes, the brain in this disorder usually being, to

1 Abeille's treatise On Albuminous and Saccharine Urine.' 2 Beale's Archives.'

3 M. Lancereaux (Bulletins de la Société Anatomique,' 1860, p. 221) describes the post-mortem examination of a diabetic subject in which the brain was softened, the ventricles dilated, and their walls discoloured, while there was much injection, with small extravasations about the calamus scriptorius, the nerve-cells being in this neighbourhood broken down and occupied by yellow granulations.

M. Luys, whose observations are alluded to above, describes the post-mortem appearances in two cases, one in the Bulletins de la Société Anatomique,' 1860, p. 247, the other in the Comptes Rendus de la Société de Biologie,' 1861, p. 24. The changes found in both were of the same kind-discoloration, vascularity, and loss of consistence in the neighbourhood of the fourth ventricle, with degeneration of the nerve-cells, which were occupied by yellow granulations.

M. Martineau ('Bulletins de la Société Anatomique,' 1861, p. 290) describes changes about the fourth ventricle similar to those previously described by M. Luys. The floor of the ventricle about the calamus scriptorius presented a greyish discoloration, with much injection of the blood-vessels.