282 THE BLOOD. 



the solid condition as a deep-violet powder which is insoluble in absolute 

 alcohol. In opposition to haemoglobin the hsemochromogen combines 

 with oxygen more firmly than with carbon monoxide. The assumption 

 of HOPPE-SEYLER that this compound is a combination of 1 molecule 

 hsemochromogen and therefore contains 1 molecule carbon monoxide 

 for 1 molecule of iron has been experimentally substantiated by HUFNER 

 and KUSTER and by PREGL. 1 



An alkaline hsemochromogen solution has a beautiful cherry-red 

 color. It shows two absorption-bands, first described by STOKES '( s P e c- 

 trum Plate 6), one of which is dark and whose center corresponds to 

 A = 556.4 between D and E, and a second broader band, less dark, which 

 covers the FRAUNHOFER lines E and b. The middle of this band 

 corresponds to A=526 to 530 according to LEWIN, MIETHE and STENGER. 

 In acid solution hsemochromogen shows four bands, which, according 

 to JADERHOLM, 2 depend on a mixture of hasmochromogen and hsemato- 

 porphyrin (see below), this last formed by a partial decomposition 

 resulting from the action of the acid. 



MiLROY, 3 from an alcoholic solution of hsematin containing oxalic 

 acid, after driving out the air by means of hydrogen gas, gradually obtained 

 an acid solution of reduced hsematin (hsemochromogen) by means of 

 .zinc dust. This solution showed one absorption-band between D and E. 



Hsemochromogen may be obtained as crystals by the action of caustic 

 soda on hsemoglobin at 100 C. in the absence of oxygen (HOPPE-SEYLER). 

 By the decomposition of hsemoglobin by acids (of course in the absence 

 of air) we obtain hsemochromogen contaminated with a little hsematopor- 

 phyrin. An alkaline hsemochromogen solution is easily obtained by the 

 action of a reducing substance (STORES' reduction liquid) on an alkaline 

 hsematin solution. An ammoniac al solution of hsematin on reduction 

 with hydrazine yields hsemochromogen very easily. An alcoholic, alkaline 

 hydrazine solution is also recommended by RIEGLER 4 as a reagent for 

 blood-pigments, converting them into hsemochromogen. 



Haeniatin, also called OXYH.EMATIN, is sometimes found in old transu- 

 dates. It is formed by the action of the gastric or pancreatic juices on 

 oxyhtemoglobin, and is, therefore, also found in the feces after hemorrhage 

 in the intestinal canal, and also after a meat diet and food rich in blood. 

 It is stated that hsematin may occur in urine after poisoning with arseniu- 

 retted hydrogen. As shown above, the hsematin is formed by the decom- 

 position of oxyhsemoglobin, or at least of hsemoglobin, in the presence 

 of oxygen. 



1 Hiifner, and Kuster, Arch. f. (Anat. u.) Physiol., 1904, Suppl. Pregl, 1. c. 



2 Nord. Med. Arkiv., 16. 



3 Journ. of Physiol., 32. 



4 Zeitschr. f . anal. Chem., 43. 



