very strong proof that these germs or organisms are carried to the intestines and there undergo changes which make them dangerous. On the other hand I think it clearly demonstrated that the germ which produces the plasmodium as found in the red corpuscles of the blood is taken directly into the lungs through the air we breathe, and enters the circulation, causing those typical cases of intermittent pneumonia, and aggravating and often producing periodical attacks of asthma.

Now, I am not going further into the consideration of the origin and development of these organisms. If I did I would only be giving you the opinion of others, as I have not investigated this part of my subject to such an extent as would warrant me in inflicting my views on you, and your time can be much better employed by looking into the works of Laveran, Councilman and Osler which are well worthy of perusal. Before considering the different types of malaria I would ask why do we have malaria in winter when the temperature is very low, if it depends on vegetable decomposition due to heat and moisture as no doubt it does? I have seen no theory advanced to account for this, and shall give you my own as expressed in a short paper read before the Sanitary Convention in London, in November, 1883. It is this: There are three great receptacles for the malarial poison, namely, the earth, the water, and the human body, that have a supply in store, as it were, laid up for the winter, which under favorable circumstances manifests itself in the shape of intermittent or other forms of malaria. The water in the wells is perhaps the greatest source of supply, particularly when the ground is frozen hard for a long time and the water gets low. The second reason is the poison escapes from under houses and spots of ground protected from the frost; and the third source is that some persons living in a malarious district have a continual supply in the system only waiting to be developed when it finds a good opportunity, such as exposure, sudden changes of temperature, over-fatigue, loss of rest, mental strain or anything else that will cause the system to run down, thus reducing and impairing the vital resistance of the nervous system. One very strong proof that these organisms are latent is that a man may have lived for fifteen or twenty years in a malarious section without ever having had ague or any other form of malaria, but let that man cross the Atlantic or go where malaria is unknown and he is liable to an attack of it. I have known many such instances which to me is a very strong proof of the latency of this germ in the blood or some of the organs of the human body.

It is true the type of malaria is milder in winter, and for the reason that the sources of supply are limited in comparison to summer, and is principally confined to localities where it is endemic; in other words, there is not enough escapes, for the winds to carry it to any distance in sufficient quantities to produce its pathological effects, if indeed it could survive the frosts it would. have to encounter on its journey. This, then, is my theory as to why we have malaria in winter. It may be erroneous, but I think the investigations of Laveran and others as to the organisms found in the blood corpuscles gives strength to this view and if this is correct goes to show that these organisms are not only a diagnostic mark but also a factor in the production of malaria. Another reason that convinces me that these are stored up in the blood or organs is this: speaking from personal experience, a sudden fall of temperature in hot weather invariably brings on in me symptoms of malaria, such as lassitude,

stretching, yawning, aching of the muscles-particularly of the back, and neuralgia, which a few doses of quiuine will relieve in a short time. The same thing occurs in cold weather on a sudden rise of temperature, and I can only account for this by having stored up somewhere in my system a supply of these, I was going to say, infernal germs or organisms. I speak feelingly and I think with some weight as I have been a sufferer in this way for over a quarter of a century.

Now, as to types of malaria. We have the quotidian, tertian, quartan and intermittent forms. Why these different types should occur is hard to explain, nor has it hitherto been satisfactorily accounted for. This is a field well worthy of further study by our pathologists. By some it is claimed to be due to individual idiosyncracies, and they offer as proof of this that in a number of people exposed to the same malarial influences, we find one having quotidian, another tertian, and a third quartan ague, as is exemplified in individuals exposed to cold under identical circumstances, one will have pneumonia, another rheumatism, and a third diarrhoea. There may be some truth in this theory, but I think that temperature as well as the intensity of infection has more to do with the different types than has individual peculiarities. My experience and investigations have led me to believe that early in the summer we have the tertian and quartan forms; when the heat is great and the emanations from the soil reach their maximum intensity we have quotidian, double quotidian and remittent; later, when the temperature is lower and decomposition has almost ceased, we go back to the quartan and tertian varieties; and still later when the temperature gets much lower we have dysentery, the reason for which I will presently endeavor to explain.

My conclusions are, then, that it is more to temperature and date of intoxication that the different types are due than to individual idiosyncracies, in proof of which it is well known and shown by statistics that in India and other tropical countries, persons that go there who have hitherto been free from malaria will have the quotidian or remittent type, while those who have lived there for years and have been exposed to, and poisoned by malaria, will have relapses at longer intervals and then only when subject to exposure or sudden change of temperature. This is, I think, important, and goes to prove that date of infection and temperature have much to do with the character and type of malarial attacks, and my own observations bear out this view. Thirty years ago almost the only form of malaria prevalent in the western district was of the quotidian and remittent variety. The latter was called bilious or biliousremittent fever, and the reason I assign for this is that the low country was almost constantly covered by water, undrained, and was being settled by emigrants who hitherto knew nothing of malaria. The land was being cleared and tilled allowing the germs to escape for the first time, so that those people got the full effect of the poison liberated from the virgin soil which had accumulated from the decayed and decaying organic matter, and as a consequence were attacked with regular old-fashioned shaking ague, that made the dishes on the table and the tins on the wall clatter. So much was this the case that it was no uncommon occurrence to find whole families laid up at once and at the same hours leaving no one to give another a drink of water. All this is now changed

and we rarely, if ever, see a case of shaking ague, but have instead chill, fever, or

dumb ague, intermittent fever, neuralgia, diarrhoea, dysentery, malarial cough, lassitude, anæmia, heart murmurs, albuminuria and œdema simulating Bright's disease, hæmaturia, enlarged spleen, rheumatic pains and congestions of nearly all the organs, besides many other affections obscure in their nature but undoubtedly due to malarial organisms. Now, how is this change in the type of malaria to be accounted for? For nearly thirty years I have been a close observer of the changes that have taken place in the forms of malarial diseases that are endemic to this section, as well as of the climatic influences which affect the character of this poison, and to my mind there are three reasons for the change. The first and chief one is better drainage. The second is that the forests have been cut down and the country cleared up lessening the amount of organic decomposition, and the third one is that nearly all the virgin soil has been cultivated over and over again, thus liberating and getting rid of nearly all the organic matter that had been accumulating and stored up under the sod.

so.

I said I would try and explain why dysentery should be produced by malaria after vegetable decomposition had ceased, and will now endeavor to do My explanation is this: Continued exposure to malaria engenders a cachectic state of the system by reducing the globular richness of the blood, and impairing the vital resistance of the nervous system, thus rendering its victims especially liable to attacks of specific febrile diseases and to splenic, hepatic, intestinal and other local congestions. One of the structures most liable to be affected is the mucous lining of the intestinal canal. Taking, then, the perverted state of the blood and tissues, the congested condition of the intestines, together with the malarial germs infesting the canal undergoing changes by fermentation and acting locally on the mucous lining as well as constitutionally through the blood, and we have made plain the reason why dysentery follows continued exposure to malarial influences, and why the mortality from this disease at such a time is far above what it would be if the malarial element had not existed.

We hear and read of typho-malarial fever. such a disease, and the name is a misnomer.

Now, I do not believe there is A person may have malarial organisms in the system and at the same time be attacked with enteric fever. As a consequence there may be and often is a chill followed by a greater rise in temperature and then a remission, but never an intermission. On examining the blood of such a patient the plasmodium will be found. By giving a few good doses of quinine the chill is arrested, but the fever goes on and runs its regular course. Again, a person living in a malarious district having typhoid, when convalescing may be attacked with malaria owing to the perverted condition of the blood and impaired state of the nervous system due to the long illness and after the enteric fever proper has run its course, but in neither of these cases can this be properly called typho-malarial fever. The bacillus of typhoid and the organism of malaria are separate and distinct poisons, and are not produced from the same causes although they enter the body by the same channels, but it has yet to be proved that the germ that produces malaria will cause typhoid, or that the bacillus that attacks the mesenteric glands and Peyer's patches will induce malaria in any form, and I think the sooner we recognize this fact the better.

My observations have taught me that if we have a continued form of fever

withstanding quinine and mild laxatives, lasting over seven or ten days, we are safe in pronouncing it typhoid, and just here let me say, that the examination of the blood corpuscles in this class of cases is one of the most valuable diagnostic marks we possess. At the same time this alone cannot be relied on, particularly where malaria is endemic, for I have seen numbers of cases undoubtedly typhoid, where in the early stage the characteristic plasmodium was found in the blood but after giving quinine for a few days they disappeared, but the fever continued and proved to be enteric, and I would impress strongly on the profession the necessity of caution in giving a diagnosis in these cases. It is much better for the physician to say I cannot tell for a few days what course this fever will take, than to give a snap diagnosis and say that this is typhoid when in the course of a week the patient will be well and at work, or on the other hand say, "Oh! this is only a case of malaria," when it turns out to be typhoid. In this case he will try to square himself with the friends by saying it was malaria but has run into typhoid, or in the former instance take to himself great credit for cutting short and curing a case of typhoid in a week. I have met with examples of both cases more than once.

One more point, and I have done. It is this: Malaria, I am convinced, is not confined to certain localities as it was twenty or thirty years ago, but it is spread over nearly all parts of the country, and is much more general than is usually supposed, and this is a very important point that must not be overlooked. Why, you may ask, is this the case when you have already proved or tried to prove that in the home of malaria, by drainage and other means before mentioned, malarial diseases have greatly decreased. My answer is this: The very means (or some of them) taken for lessening the supply at the fountain head has, while accomplishing this object to a certain extent, caused it to be carried by wind, water and rail to the homes of thousands who before were strangers to this disease. The country having been cleared of its forests (themselves great consumers of these emanations) allow the winds to have free sweep wafting the germs miles and miles from their original lair. The water, in the new-made drains, carries the poison to streams and rivers to be used in many a household. The railways, conveying as they do, thousands of passengers long distances from the source of malaria, many of whom have these organisms latent in the body, which are only developed on reaching their destination owing to climatic changes or other causes, are great distributors of this disease, introducing it in this way to localities where perhaps hitherto it had been entirely unknown, and while the types of malaria are not so well marked as was the case when confined to certain districts (the poison being less concentrated), only makes its diagnosis more difficult, and often accounts for the seeming obscurity of many affections that puzzle and perplex the busy practitioner.

THE IDENTITY OF DIPHTHERIA AND MEMBRANOUS CROUP.*
By W. LYNN WILSON, M. D., DETROIT, MICHIGAN.

THE question whether diphtheria and membranous croup be distinct diseases, is one which has occasioned much discussion, and concerning which there has been great difference of opinion.

*Read at a stated meeting of the DETROIT MEDICAL AND LIBRARY ASSOCIATION, and published exclusively in The Physician and Surgeon.

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The majority of opinion seems to be in favor of regarding them as distinct diseases, and in the majority of text-books we find them described in separate articles, membranous croup being defined as a local disease, characterized by fibrinous inflammation of the upper air passages; diphtheria an infectious disease with, in certain cases, a similar localization of the fibrinous exudation. But on reading the articles we cannot help but be struck by the fact that the authors themselves are not very clear on the subject. Argument advanced in one paragraph is frequently contradicted in the next. For instance, Flint says: "It is an established fact that pseudo-membranous inflammations of the throat may be produced by the special poisons of various infectious diseases, as scarlet fever, measles, and small-pox." In the very next paragraph, we read: "A diphtheritic affection of the throat often occurs as an element of scarlatina, and the two diseases may exist in combination. This is the probable explanation of reported instances in which patients with scarlet fever apparently communicated diphtheria and vice versa;" and he then relates the case of a boy, aged four years, who had well-marked diphtheria and no eruption. After convalescence he became affected with complete hemiplegia and general dropsy. He had the sequels of both scarlatina and diphtheria following what appeared to be purely an attack of the latter, and he communicated to his sister scarlatina and not diphtheria.

Their names throw no light on the subject. The word croup is of Scotch origin, and signifies strangulation, a symptom in certain cases, common to both diseases. Diphtheria comes from a French word diphtherite, the significance of which relates to the most characteristic local event, the deposition of a false membrane, which likewise is a symptom of both affections. Let us now compare the two diseases, as described by most authors, in their anatomical characters, their etiology, pathology, clinical history, and the results obtained in their treatment.

Anatomically considered, a croupous exudation signifies a fibrinous false membrane, which rests loosely upon the mucous membrane without extending into its substance; the necrosis involving only the epithilial covering, while a diphtheritic exudate is a fibrinous false membrane, which is closely adherent to the mucous membrane, and cannot be stripped from it without loss of substance, the necrosis involving not only the epithelium, but also the superficial layers of the mucous membrane. These terms are used without any reference to the diseases known as croup and diphtheria, for in both these affections the exudation when seated in the trachea or lower portion of the larynx is of the croupous variety but, when seated on the tonsils, palate, or pharynx, of the diphtheritic variety, the difference appearing to depend on the kind of epithelium with which the parts are covered, the false membrane being readily separated from mucous membranes covered with cylindrical epithelium as in the bronchi, trachea, and greater part of the larynx, while on those covered with the laminated. flat epithelium, as upon the tonsils, palate and pharynx, it is more adherent. In croup the larynx is by preference attacked, but it is usually accompanied by fibrinous exudation in the pharynx or the false membrane may first appear there and afterward invade the larynx. In diphtheria the tonsils, palate or pharynx are usually first attacked, but frequently the false membrane also invades the larynx, and in this case those who favor the duality of the diseases say that croup occurs as a complication of diphtheria, which appears to be irrational. If