Abstract
Abnormal agglutinability of the erythrocytes was observed in 2 cases infected with pyogenic micro-organisms. In Case 1 the abnormality was transient and the patient recovered. In Case 2 auto-agglutination was present at body temp. The patient died and at autopsy signs of intravital hemolysis and a non-septic thrombus in the left internal carotid artery were found. It is supposed that these cases constitute examples of an intravital Hubener-Thomsen phenomenon.