DEFINITION.--An endemic infectious fever, usually lasting between three and four weeks, and associated with constant lesions of the solitary and agminate glands of the ileum, and with enlargement of the spleen and mesenteric glands. Its invasion is usually gradual and often insidious. Sometimes the only symptoms present in the beginning are a feeling of lassitude, some gastric derangement, and a slight elevation of temperature; at others there are slight rigors or chilly sensations, headache, epistaxis, diarrhoea, and pain in the abdomen. The principal symptoms of the fully-formed disease are a febrile movement possessing certain characters, headache passing into delirium and stupor, diarrhoea associated with ochrey-yellow stools, tympanites, pain and gurgling in the right iliac fossa, a red and furred tongue, which later often becomes dry, brown, and fissured; a frequent pulse; an eruption of rose-colored spots, occurring about the seventh or eighth day, slightly elevated above the surface, disappearing under pressure, and coming out in successive crops, each spot lasting about three days; prostration not marked in the beginning, but rapidly increasing; and occasionally deafness, sweats, and intestinal hemorrhages. When recovery takes place, the convalescence is usually tedious, and may sometimes be protracted by the occurrence of one or more relapses. SYNONYMS.--The following are a few of the many names which have been given to the disease at different times. Most of them have ceased to be applied to it, and only three or four of them are at present in general use: Febris Mesenterica, 1696; Slow Nervous Fever, 1735; Febricula or Little Fever, 1740; Typhus Nervosus, 1760; Miliary Fever, 1760; Typhus Mitior, 1769; Synochus, 1769; Common Continued Fever, 1816; Gastro-Enterite, 1816; Entero-Mesenteric Fever, 1820; Abdominal and Darm Typhus, 1820; Typhus Fever of New England, 1824; Dothienterie, 1826; Enterite-folliculeuse, 1835; Infantile Remittent Fever, 1836; Enterite Septicémique, 1841; Mucous Fever, 1844; Enteric Fever, 1846; Intestinal Fever, 1856; Ileo-Typhus, 1857; Pythogenic Fever, 1858; Mountain Fever, 1870.