CHAP. V.] THE ORIGIN OF THE BILE COLOURING MATTERS. 349 



The origin of As soon as the" remarkable resemblance, if not the 

 the bile colour- ^ absolute identity, of Virchow's hsematoidin with bili- 

 )rs ' "rubin was pointed out, the clue to the origin of the 

 bile colouring matters was discovered. 



"In extravasations of blood, the colouring matter of the blood disappears 

 and in place of it we find a crystallised pigment, which Virchow l was the 

 first to examine carefully and named hsematoidin. The same writer 

 pointed out its resemblance to bile pigment 2 . Subsequently Robin 3 , Jaffe 4 

 and Salkowski 5 proved the identity of hsematoidin and biliverdin. 

 Langhans 6 took the blood from the vein of a living pigeon and injected it 

 under the skin of the same animal ; after two or three days the colouring 

 matter of the blood had disappeared from the subcutaneous clot and was 

 replaced by bilirubin and biliverdin. Quincke 7 performed the same experi- 

 ment on dogs. In this case the conversion occupied more time : the 

 bilirubin did not appear in the subcutaneous injection before the ninth 

 day. Cordua 8 injected blood into the abdominal cavity of dogs and found 

 bilirubin after so short a time as thirty-six hours. Finally Recklinghausen 9 

 has seen bile pigment formed in the blood of frogs outside the body, after 

 from three to ten days 10 ." The observations here recorded have been 

 confirmed and extended by the experiments of Latschenberger 11 who 

 injecting the blood corpuscles of the horse, or a magma of haemoglobin 

 prepared from horse's blood into the subcutaneous areolar tissue of another 

 horse found, after some days, reddish yellow pigments (Choleglobine) at 

 the seat of injection, and in addition dark pigmentary matter containing 

 iron (1) which he designated 'Melanin ' ; Neumann 12 had previously found a 

 similar pigment in blood extravasations and thrombi in man and had 

 designated it hcemosiderin. According to Kunkel 13 , the latter consists of 

 ferric hydrate. 



A study of the empirical formulae of hsematin and of bilirubin 

 shewed 14 how closely bilirubin resembled in composition an iron 

 free haematin. According to Nencki and Sieber 15 , the following 



1 Virchow's Archiv, Vol. i. (1847), pp. 379, 407. 



2 Virchow, loc. cit. p. 445. 



3 Robin, Comptes Eendus, Vol. XLI. (1855), p. 506. 



4 Jaffe, Virchow's Archiv, Vol. xxm. (1862), p. 192. 



6 Salkowski, Hoppe-Seyler's Med. chem. Unters. Heft m. (1868), p. 436. 



6 Langhans, Virchow's Archiv, Vol. XLIX. (1870), p. 66. 



7 H. Quincke, Virchow's Archiv, Vol. xcv. (1884), p. 125. 



8 Herm. Cordua, ' Ueber den Resorptionsmechanismus von Blutergiissen. ' Berlin, 

 Hirschwald, 1877. 



9 Recklinghausen, Handbuch d. allgem. Path. d. Kreislaufes und der Ernahrung, 

 p. 434. Stuttgart, Enke, 1883. 



10 Bunge, Op. cit., p. 376. 



11 Latschenberger, 'Die Bildung des Gallenfarbstoffes aus dem Blutfarbstoff. ' 

 Monatschrift f. Chemie, Vol. ix. (1888), p. 52. Quoted by Neumeister, Lehrbuch der 

 physiologischen Chemie, p. 174. 



12 Neumann, ' Beitrage zur Kenntniss der pathologischen Pigmente.' Virchow's 

 Archiv, Vol. cxi. (1888), p. 25. 



13 Kunkel, ' Ueber das Vorkommen von Eisen nach Blutextravasation. ' Zeitschrift 

 f. phijs. Chemie, Vol. v. (1881), p. 40. 



14 Kiihne, Lehrbuch, p. 203. 



15 Nencki und Sieber, ' Untersuchungen iiber den Blutfarbstoff.' Ber. d. deutsch. 

 chem. GeselUchaft, Vol. xvn. (1884), p. 2275. 



