With the exception of the intermittent, the most common form of fever prevalent in the middle, southern, and south-western sections of the United States, is the remittent, or as it is generally called, the Bilious Remittent, or, simply, Bilious fever. It constitutes the summer and autumnal epidemic of many of the States, and even in those which are exempted from its annual occurrence, it occasionally prevails, during seasons of unusual heat and dryness, sporadically, or as a severe and widely-spread epidemic. And strangers coming from cooler sections of country are particularly liable to be attacked.

The milder and more simple form of Bilious Remittent Fever, is generally preceded, for some days, by listlessness, languor, a bitter taste in the mouth, nausea, aversion for food, an indescribable uneasiness and sense of fulness about the stomach, sometimes costiveness, and very generally more or less pain and heaviness over the eyes. The attack is usually ushered in by a slight chill, or merely by a sense of coldness, particularly about the back, which, after one or more hours, and often sooner, is followed by increased heat of the whole surface, the skin becoming at the same time, dry and constricted, the face flushed and turgid, the eyes red and suffused, the breathing hurried and uneven, the pulse quick but rarely hard; there is great prostration of strength with considerable restlessness and watchfulness. The patient complains of pain and a sense of fulness, weight and tightness the head, pain in the back and in the extremities, particularly in the calves of the legs. The stomach is more or less irritable. Vomiting is not unfrequent; it is sometimes present from the commencement of the attack, but generally it does not set in until the second or third day, or even later; the matter vomited being of a bitter taste, and of a yellow, greenish, or bright green colour. The tongue is usually moist, red at the sides and edges, and coated on its upper surface with a whitish, light-brown, or yellowish fur, which often acquires considerable thickness. There are usually considerable thirst, costive bowels, scanty and high-coloured urine, and, after the disease has continued for some days, the skin acquires a yellow tinge, which extends to the eyes. After from eight to twelve hours, a gradual abatement of all the prominent symptoms takes place, and often a slight moisture breaks out upon the surface, and the patient falls into a refreshing sleep; more generally, however, the skin continues dry after the heat has declined, and the patient during the remission continues restless, uneasy, and disinclined to sleep.

The duration of the remission varies with the violence of the attack: gradually, however, the heat of the surfaces increases, and a return of the fever follows, marked by the same degree of intensity as the former one, or even by increased violence. All the preceding symptoms, in an aggravated degree, with long-continued fits and less distinct remissions, mark what has been termed the highly inflammatory form of the disease. During the fit the skin is intensely hot, the eyes are suffused, of a muddy, yellowish hue, and often dull and languid; there are intense pain, and a sense of insupportable weight and tightness of the head; a dislike to light and noise is usual, and sometimes there is delirium, there are great thirst, with oppression at the chest; the breathing is quick and laborious, frequently irregular: the pains in the back and extremities are often severe; the pulse is quick and hard, occasionally irregular; the nausea and vomiting are generally distressing, the matter discharged being a thick ropy fluid, of a yellow, darkish-brown, or green colour; the bowels are costive, or if open, discharge, with tenesmus and griping, a thin, watery fluid; when evacuations are procured by appropriate means they are large in quantity, dark, slimy, tenacious and offensive. There is always a great sense of oppression at the stomach, with a degree of tenderness which renders the slightest pressure insupportable; or a severe pain and burning, with great nausea, and frequent ineffectual efforts to vomit. In the course of the disease, the skin acquires generally, a brownish, bronzed, or more frequently a deep yellow tinge, which is particularly marked upon the face and breast.

The succeeding exacerbations are marked by increased violence of the symptoms, and unless the intensity of the fever is relieved by an appropriate course of treatment, the powers of life gradually sink; the surface, at length becomes cool, and covered, generally or partially, with a cold, clammy sweat; the pulse small and weak; the tongue covered with a dark, thick coating, and occasionally dry and chapped; the breathing short, quick and difficult; the abdomen sometimes swollen and tympanitic; stupor or insensibility often ensues; and at length involuntary discharges take place from the bowels of a dark offensive matter, and finally death closes the scene.

The duration of the disease varies with its degree of violence, and its simple or complicated character; it may terminate in a few days, or run on for several weeks; but its usual duration is from nine to fifteen days. "It is not uncommon," Dr. Dickson, of South Carolina, remarks, "especially among the most perfectly acclimated adult natives resident in malarious localities, and strangers long familiarised to these, to find bilious remittent fever of a very protracted duration; the patient sinking, after the tenth or twelfth day, into a low form, resembling the less severe grades of typhus, and hence obtaining among us the designation of the typhoid stage of bilious fever."

There is one form of bilious intermittent, which is known in the southern and south-western portion of the United States under the name of Congestive fever. "In certain localities indeed," remarks Dr. Dickson, "the ancient inflammatory features of malarious endemics seem to have disappeared, and to have become supplanted by the more hideous and pestilential modification thus entitled."