548 CHEMISTRY OF THE PROTEIDS CHAP. 



not contain tryptophane. Sodium chloride does not salt out ovi- 

 mucoid, while sodium- and magnesium -sulphate do so on boiling ; 

 precipitation with ammonium sulphate commences in -- saturated 

 solutions, and fully saturated solutions are required for a complete 

 separation. When boiled with acids, a reducing substance is split 

 off, which has been carefully investigated by Friedrich Miiller and 

 Seemann; 1 this reducing radical is identical with the glucosamin 

 which may be obtained from true mucins, but the glucosamin does not 

 occur in the molecule as such, according to Steudel. 2 Out of 100 

 grammes ovi-mucoid Seemann obtained 2 9 -4 grammes of glucosamin. 

 Amongst the dissociation -products he obtained acetic acid and a 

 di-ethyl-sulphino-fatty acid. Weydemann 3 prepared from ovi-mucoid 

 Landwehr's ' animal gum,' which resembles that obtainable from mucin 

 and pseudo-mucin. 



5. Serum-mucoid 



Zanetti 4 found in blood-serum a mucoid, which closely resembles 

 ovi-mucoid in its properties and in its composition. Its presence must 

 be taken into account when working at the separation of sugar-radicals 

 from serum-albumin. 



6. Mucoid from Urine 



A mucoid which also resembles ovi-mucoid, but which is more 

 nearly related to the mucins, being precipitable by acetic acid, has 

 been isolated by K. A. H. Morner 5 from human urine. From 260 

 litres he obtained 4 '3 grammes. It is partly in solution and partly in 

 the form of the so-called ' nubecula.' In some animals it is replaced by 

 a nucleo-albumin, and the nucleic acid from the leucocytes of the urine 

 has also a mucilaginous character (see there). Stahelin 6 describes a 

 body having somewhat different properties, as occurring occasionally 

 in the urine. 



7. Mucoid from Ascitic Fluid 



A number of ascitic fluids formed during different etiological con- 

 ditions have been investigated by Hammarsten, 7 Paijkull, 8 Umber, 9 and 



1 J. Seemann, Dissertation, Marburg, 1898 ; F. Miiller and J. Seemann, Deutsche 

 med. Wochenschr. 1899, p. 209 ; F. Miiller, Zeitschr.f. Biol. 42. 468 (1901). 



2 H. Steudel, Zeitschr. f. physiol. Chem. 34. 353 (1901). 



3 H. Weydemann, Dissertation, Marburg, 1896. 



4 C. U. Zanetti, Ann. di Chim. e Farmac. 12. According to Maly's Jahresber. /. 

 Tierchem. 27. 31 (1897). 



5 K. A. H. Morner, Skandinav. Archivf. Physiol. Q. 332 (1895). 



6 Stahelin, Munchener med. Wochenschr. 1902, p. 1412. 



7 0. Hammarsten, Zeitschr. f. physiol. Chem. 15. 202 (1891). 



8 L. Paijkull, Maly's Jahresber. f. Tierchem. 22. 558 (1892). 



9 F. Umber, Zeitschr. f. klin. Med. 48. Hefte 5 and 6 (1903) ; Munch, med. 

 Wochenschr. II. p. 1169 (1902). 



