Abstract
A method is descr. for colorimetric detn. of methemoglobin in circulating blood based on the difference of light absorption between methemoglobin and cyanmethemoglobin in the red spectral region (618 mmu). Using concentrated solns. in the Beckmann quartz spectrophotometer, a sensitivity of 0.02 g. methemoglobin/ 100 ml. of blood was attained. The content of methemoglobin in the blood of various mammals detd. by this method are listed.