attacked, and according to the condition of the patient. The parasite seems to act upon the capillaries of the subjacent tissue; as, when removed, blood is not uncommonly effused, and the surface looks raw. Diphtheria is not, however, necessarily limited to one form of disease. We have, in fact, had a case of syphilitic disease of the fauces and pharynx, in which the pellicle containing the oidium was noticed, and which seems to have introduced it into the clinical wards. Again, if the fungus multiply in a population, at the same time that there is an epidemic of scarlatina or rubeola prevalent therein, that epidemic may be expected to take the diphtheritic form in those cases which are attacked by the oidium. I must add, however, that we have reasons for thinking that the oidium, acting alone, will fasten upon the mucous membrane of the mouth and throat, and excite inflammation, and without the formation of a pellicle. Or, if it lead to the formation of a pellicle, this may be constituted of spores only, with exudation of corpuscles, constituting a tougher membrane than that usually found on the tongue and tonsils, and resembling the pellicle of croup.

"The diagnosis of diphtheritic oidium from ordinary aphthæ is founded, first, on the character of the morbid appearance; for, in ordinary aphthæ, the disease is vascular, and the white specks or patches are ulcers, while in diphtheria they are pellicular, and not ulcerative, while the redness is much deeper than in aphtha. Besides, the microscope may reveal the spores and mycelium of the fungus. The development of mycelium is, however, by no means a necessary result of the action of the fungus. This seems to be a feature peculiar to the more advanced stages; at first, there is not even a pellicle, only characteristic redness of the affected surface. Dr. Young, our resident physician, got an attack of sore throat, shortly after one of the patients affected with oidium coughed in his face, while he was applying a remedy to the patient's fauces. Dr. Young had this characteristic deep-red congestion of the fauces, with but very limited production of pellicle on the pharynx, in which no mycelium was to be discovered. Further, it is

probable that, besides the stage of development, the condition of the habitat may make a considerable difference as to the morbid products. Thus, since warmth greatly promotes the spread of the disease in the form of muguet, the absence of mycelium in diphtheritic croup may be due either to the fact, that the weather is cooler when it prevails, or that the mucous membrane of the larynx and trachea, being cooler generally, from the transit of air, is less favorable to the development of the mycelium, than that of the mouth, fauces and œsophagus.

"Again, the condition of the intestinal mucous membrane seems less favorable to the formation of the mycelium, or of a pellicle upon it. Still, inflammation and even ulceration of the surfaces will occur, as the result of the irritative action of the parasite, in the same way as ulcerative inflammation supervened in the oesophagus of the patient in question. This remark applies, also, to the bronchial mucous membrane, in which, I am inclined to think, the oidium may develop an inflammation of the same low type as that seen elsewhere, asthenic bronchitis with a purulent secretion."

an

In connection with this subject, I cannot help extracting the important observations of Dr. Wilkes, assistant physician to Guy's Hospital.1

Dr. Wilkes took the opportunity to examine the films which occasionally form on the mouths of those sick with various diseases, and on submitting them to the test of the microscope, felt some surprise in witnessing in all fungus growth which he had not been able to distinguish from that of diphtheria. Thus he lately had a woman die under his care, in Guy's Hospital, with acute cerebral and spinal meningitis, pleuritis, &c., of a supposed phlebitic origin, and on examination of the pharynx, after death, a pellicle was found composed of the parasite. Again, a child four years old presented itself among his out-patients, apparently dying with croup, but on examination was found to be suffering from an extension of diphtheritic disease into the trachea. The throat and

Medical Times and Gazette, October, 1858.

tongue were covered with pellicle, a portion of which being placed under the microscope displayed very readily the oidium, the only difficulty about the case being the statement of the mother, that the child had suffered with a throat affliction for several weeks. Mr. Hardy made a post-mortem examination. The throat, trachea, &c., were covered with a pellicle, as before said; and on removing this, to find a cause for the chronic symptoms, a polypus of a capillary character was seen growing from one of the vocal cords, with thickened tissue around. Here was an explanation of the chronic symptoms; and upon this had arisen an acute inflammation, accompanied by the fungus. Another case was that of a man who died under Dr. Wilkes' care, in the hospital, with softening of the spinal cord. A few days before his death his mouth and tongue became covered with a white secretion, which very rapidly formed a complete layer over the whole buccal surface. An examination of this by the microscope showed a remarkably fine specimen of the fungus, the mycelium and sporules exhibiting themselves to perfection. On mentioning these circumstances to Dr. Barlow, he stated that he had under his care a child with a white film on his mouth, (the case not being one of diphthérite,) and he sent some of the secretion for examination, when it was found to resemble the specimens already named; the same occurred in one or two other cases. These facts are sufficient to show that a vegetable fungus may spring up on the buccal mucous surface in various cases of disease, but requiring, probably, some previously morbid condition for a nidus. Is it not so in diphthérite? Is the disease, strictly speaking, a malignant sore throat, and the formation of the pellicle an accident? Or is the latter an essential part of the affection? In the case of the child last mentioned, if no post-mortem examination had been made to discover the chronic disease, the case would have been called diphtheria; and in the man with spinal paraplegia, the condition of the mouth would have been sufficient to have marked it a case of the same kind, had there been no other affection present. Such cases may throw some light upon the opinions of those

practitioners who, not residing in diphtheritic districts, and who, seeing only isolated cases, regard the disease as a mere modification or peculiar form of some ordinary maladies, as cynanche and scarlatina, and this may, in some instances, be correct.

In speaking of the parasitic growth found in the abovementioned instances, we are aware of the objection which can be made, that the fungus of diphtheria is peculiar, (supposing it always to be present,) and that found in the mouth and throat of other sick persons is in connection with aphthae, and is another variety. In answer, Dr. Wilkes says that he failed to discover in the above cases any difference; and, moreover, the character of the pellicle, and its rapid extension over the whole mouth, throat and tongue, was totally unlike ordinary aphthae. Dr. Slade, in his essay, gives a picture of the diphtheritic pellicle, as examined under the microscope, and the sporules and the mycelium of the oidium, (after Robin,) and the two are in appearance almost identical. Dr. Francis Black says: "I examined only one specimen of membrane, assisted by a friend who is daily engaged in the microscopic study of plants; but we were unable to discover the least appearance of vegetable structure. The same microscopist also informed me that the same results were met with by a friend who examined upwards of a dozen different specimens.”

My friend, Coleman Sellers, took great pains to examine, by his powerful microscope, some specimens of diphtheritic membrane; but we could arrive at no definite conclusions about their nature. There certainly appeared to be no vegetable

structure.

DIAGNOSIS.

Diphtheria is considered by some physicians to be analogous to dysentery, by others, to malignant scarlatina and croup. That there are great affinities between it and these diseases is undeniable; but it is difficult to establish the identity of their ultimate essence.

G-Diagnosis between Diphtheria and Scarlatina.

Those who have carefully read my classification of the dif erent forms of diphtheria, must have come to the conclusion with me that the disease has manifested itself in various forms since its first appearance in Philadelphia. At first, being very virulent, it attacked principally the fauces and larynx, and finally the brain, and was often suddenly fatal. At a later period, when it diffused itself throughout the system in a milder form, it was more manageable, although deaths would still occur from the more violent cases of this kind. During the year 1861 the greatest number of deaths from scarlatina occurred, as well as from diphtheria, namely, one thousand one hundred and ninety of the former, and five hundred and two of the latter. The same or similar causes must, therefore, have been productive in originating these two diseases. The fact is, the more I consider the matter the more the opinion gains ground that these two diseases, and perhaps, also, croup, are only modifications of the same poison, as we know the common bilious fevers of a country are only modifications of the violent yellow fever, and the same remedies will often be able to subdue them; scarlet fever being the most violent form of the disease, and scarlatina and croup manifestations of the same poison in different forms.

In the diagnosis of the two diseases by different writers, the main stress is laid upon scarlatina seldom or never attacking the larynx and bronchia. We have seen, by one classification, that some forms of diphtheria attack the stomach, the intestines, and even the anus, but still the nature of the poison may be the same. Dr. Slade, of Boston, in his prize essay, says: "By some persons, the two affections scarlet fever and diphtheria, notwithstanding certain points of strong resemblance, are regarded as essentially different. By others, diphtheria is regarded as a form of scarlet fever, in which the throat affection is unaccompanied by the eruption which usually characterizes it. We must admit that there are many circumstances which favor this latter opinion. For in