634 ORGANS OF GENERATION. 



conalbumin is a mixture or not, and the question concerning the unity 

 of the crystallizable ovalbumin is also disputed. According to BOND- 

 ZYNSKI and ZOJA, crystallizable ovalbumin is a mixture of several albumins 

 having somewhat different coagulation temperatures, solubilities, and 

 specific rotations, while HOFMEISTER and LANGSTEIN on the contrary 

 believe that crystallizable ovalbumin is a unit. The reports as to the 

 specific rotation of the different fractions unfortunately differ, and the 

 elementary analyses have also given no positive results, as a variation 

 of 1.2-1.7 per cent has been observed in the quantity of sulphur. Accord- 

 ing to the consistent analyses of OSBORNE and CAMPBELL and of LANG- 

 STEIN, the conalbumin contains about 1.7 per cent sulphur and about 

 16 per cent nitrogen, while the ovalbumin contains on an average about 

 15.3 per cent nitrogen. LANGSTEIN 1 obtained 10-11 per cent glucosa- 

 mine from ovalbumin and about 9 per cent from conalbumin. The 

 ovalbumin, like the conalbumin, has the properties of the albumins in 

 general, but differs from seralbumin in that the specific, rotation 

 is lower. It is quickly made insoluble by alcohol and is precipitated 

 by a sufficient quantity of HC1, but dissolves in an excess of acid with 

 greater difficulty than the seralbumin. The products isolated by 

 ABDERHALDEN and PREGL 2 on the hydrolysis of ovalbumin do not show 

 anything of special interest. 



As in the past certain doubts have existed as to the purity and chem- 

 ical unity of the ovalbumins, or also of the crystalline ovalbumin, so now 

 this doubt has become still stronger since ovalbumin has been pre- 

 pared partly free from phosphorus and partly with a variable phos- 

 phorus content of 0.1-3.06 per cent (KAAS, WILLCOCK and HARDY 3 ). 



In preparing crystalline ovalbumin, mix, according to HOFMEISTER, 

 the beaten white of egg free from foam with an equal volume of a saturated 

 ammonium-sulphate solution, filter off the globulin, and allow the filtrate 

 to evaporate slowly in thin layers at the temperature of the room. After 

 a time the masses which separate out are dissolved in water, treated 

 with ammonium sulphate-solution until they begin to get cloudy, and 

 are allowed to stand. After repeated recrystallization the mass is either 

 treated with alcohol, which makes the crystals insoluble, or they are 

 dissolved in water and purified by dialysis. From these solutions the 

 proteid does not crystallize again on spontaneous evaporation. (See also 

 page 633, footnote 2, for the HOPKINS and PINKUS method.) WILL- 

 COCK 4 has recently found that magnesium sulphate can also be used in 

 the crystallization of ovalbumin. 



1 Zeitschr. f. physiol. Chem., 31. 



2 Ibid., 46. 



3 Kaas, Monatsh. f. Chem., 27; Willcock and Hardy, cited from Chem. Centralbl.. 

 1907, 2, 821. 



4 Journ. of Physiol., 37. 



