ONE PLATE (TEN FIGURES) Recent studies have shown that many cells other than those of recognized phagocytic capacity may take up particulate matter such as carbon and carmine. I n a study of the blood of the leopard frog following injections of India ink into the dorsal lymph sac, Jordan ( '25) found that monocytes phagocytosed the greatest amount, while neutrophiles took up only minute particles and lymphocytes and young thrombocytes might contain a few grains. The present study deals with the leucocytic reaction in Necturus to large amounts of carbon, in the form of Higgin's waterproof India ink, injected intravascularly.
MATERIALS AND METHODSMature, medium-sized, specimens of Necturus maculosus were used. The India ink was diluted with three volumes of distilled water and filtered twice. All injections were made by way of afferent branchial arteries. Two animals received two successive daily injections of 0.25 cc. of the suspension and were killed 24 hours later. Two others received similar injections, with a 48-hour interval, and were killed, one 48 and the other 120 hours after the last injection. A fifth animal was given a n 0.75 cc. injection, followed in 48 hours by a n 0.25 cc. injection, and was killed 96 hours later.