x THE GLYCO-PROTEIDS : MUCIN 539 



them pseudo-mucins. Later on they were also studied by Oerum, 1 

 Pfannenstiel, 2 Leathes, 3 Zangerle, 4 Steudel, 5 Neuberg and Heymann, 6 

 and Otori. 7 



In normal Graafian follicles, and also in the so-called hydrops 

 ovarii, Pfannenstiel found only albumins, presumably serum-albumin 

 and serum-globulin, while the proliferating, papillary, or glandular 

 cystomata always contain, according to Oerum and Pfannenstiel, 

 pseudo-mucin, which imparts to them a more or less mucous or viscous 

 character. 



Pseudo-mucin, prepared by precipitation with alcohol, according to 

 Hammarsten's method, from cystomic fluids containing no or very little 

 albumin, is a fine, white, very hygroscopic powder. It is readily 

 soluble in water, and if present in low concentrations behaves like 

 mucin ; in stronger concentrations Oerum found in ovarial cystomes 

 0'88 to 10'83 per cent albuminous bodies it forms a whitish, tough, 

 and mucilaginous fluid resembling a thick gum-solution. By acidifica- 

 tion with acetic acid or hydrochloric acid, pseudo-mucin is not pre- 

 cipitated, and thus differs from the true mucins ; neither does nitric 

 acid precipitate, but it renders the solution more opalescent and more 

 viscous. Otherwise pseudo-mucin gives the reactions of true mucins : 

 it is not precipitated by ferrocyanic acid or by being boiled, but it is 

 precipitated by lead acetate, mercuric chloride, and tannic acid. The 

 two reagents last mentioned do not produce, however, a true floccula- 

 tion, but only lead to the formation of a mucilaginous jelly. Alcohol 

 gives rise to a tough curd, as it does in solutions of mucin ; pseudo- 

 mucin is only slowly denaturalised by alcohol. 



Pseudo-mucin gives the xantho-proteic reaction and those of Millon 

 and Adamkiewicz. It is not precipitated by magnesium sulphate, even 

 if the reaction be acid, and when boiled with acids liberates glucosamin, 

 which, according to Zangerle, is identical with the glucosamin pre- 

 pared from true mucin ; he obtained 30 grammes of glucosamin from 

 100 grammes of pseudo-mucin. Neuberg and Heymann found consider- 

 able quantities of glucosamin, and believe that the other carbohydrates 

 mentioned by Leathes are absent. The dissociation-products T which 



1 H. P. Oerum, Mcdtfs Jahresbericht f. Tierchemie, 14. 459 (1884). 



2 J. Pfannenstiel, Arch. f. Gyndk. 38. 407 (1890). 



3 J. B. Leathes, Schmiedeberg' s Archiv f. experiment. Pathol. und Phannakol. 43. 

 245 (1899). 



4 Zangerle, Munchener med. Wochenschr. 1900, p. 414. 



5 M. Steudel, Zeitschr. f. physiol. Cliem. 34. 353 (1901), (good account of older 

 literature bearing on the carbohydrate-radical). 



6 C. Neuberg and F. Heymann, Hofmeister's Beitrage, 2. 201 (1902). 



7 J. Otori, Zeitschr. /. physiol. Chem. 42. 453 (1904). 



