Stegemann (1914) described pathological changes in the myocardium and nervous system of the heart. Siegmund (1931) found inflammation chiefly in the thebesian vessels. Brody and Smith (1936) found pathological changes in the heart of 90 per cent. of the fatal cases. They described three types of myocarditis: 1. Focal or diffuse interstitial myocarditis. 2. Arteritis or periarteritis of the smaller coronary arteries. 3. An infiltration of the coronary veins or of the endocardium of the ventricles. Albert (1938) found myocarditis in four cases among eight children who died of scarlet fever. Toomey (1942) found haemorrhages in the bundle of His in a case of auriculo-ventricular block. Five cases of double infection of scarlet fever and diphtheria were examined by the same author: myocarditis was found in two cases. Among the clinical reports Nobecourt's paper (1918) must be mentioned; he found two out of seven soldiers who had clinical signs of endocarditis and developed signs of permanent damage in the heart. Thursfield (1929) found carditis especially in cases of scarlet rheumatism and he noticed permanent damage in some of the cases. The cardiac complications due to scarlet fever without scarlatinal rheumatism are regarded by him as temporary and he did not see permanent damage in these cases. Rolleston (1912) noticed a fall in blood pressure in 25 per cent. of the cases after an initial rise in the beginning of the disease. He found (1929) the incidence of endocarditis below one per cent.; myocarditis was more common and this was manifested by rapid and small pulse, feeble heart sounds and gallop rhythm, but no data of its incidence could be given. Stoeber (1935) described his main clinical findings in myocarditis in scarlet fever as: cardiac enlargement, soft systolic apical murmur and arrhythmia. He attributed sudden death in scarlet fever to an acute myocarditis. Wyborn (1934) out of a series of 2,300 cases at the South Eastern Hospital discovered only four cases of arrhythmia, one being a case of auricular fibrillation and the other three just simple arrhythmia. Out of 600 cases of scarlet fever Faulkner (1935) had seven that developed signs of chronic valvular disease. In two of his cases the signs of endocarditis developed in hospital before discharge.