CERTAIN DERIVATIVES OF THE PROTEIDS. 317 



PERCENTAGE COMPOSITION OF THE ASH-FBEE SUBSTANCE. 



L H. in. IV. V. Average. 



C 51.05 50.82 ... ... ... 60.93 



H 6.84 ... ... ... ... 6.84 



N ... ... 13.61 13.56 . . . 13.58 



S ... ... ... ... 1.62 1.62 



O ... ... ... ... ... 27.03 



100.00 



This is the only analysis, so far as we are aware, of an 

 antipeptone prepared from pure antialbumid. Some years ago 

 Kiihne and Chittenden* analyzed a preparation of so-called 

 antipeptone prepared by the digestion of antialbumid with 

 alkaline pancreatic juice, but at that tune the proteoses had 

 not been discovered and consequently the method of separa- 

 tion made use of did not effect the removal of the antialbu- 

 moses; hence, the product analyzed was without doubt a 

 mixture of true antipeptone and antialbumoses. In consider- 

 ing the composition of this product it will be remembered 

 that antialbumid is characterized by a comparatively high 

 content of carbon and a low content of nitrogen (53.79 per 

 cent C and 14.55 per cent N),f hence it is to be observed that 

 in the formation of this peptone, as in all cases of peptone 

 formation, the mother proteid loses an appreciable amount of 

 carbon.}: Somewhat noticeable in this product is the com- 

 paratively high content of sulphur, for peptones as a rule 

 contain a very small amount of this element. There was no 

 sulphur, however, present in the mercaptan form, and the ash 

 contained no sulphate. Neither was there any evidence of 

 the presence of ammonium sulphate. As to the relationship 

 in composition between this antipeptone and the antipeptone 

 resulting from the pancreatic digestion of a native proteid it 

 will suffice here to refer the reader to previous papers on 

 antipeptone. 



* Kiihne and Chittenden, Zeitschr. f. Biologie, 1883, xix, p. 169. 

 t Kiihne and Chittenden, loc. cit., p. 167. 



t See Chittenden, Digestive Proteolysis, New Haven, 1895, p. 70. 

 Kiihne and Chittenden, Zeitschr. f . Biologie, 1886, xxii, p. 423 ; Chitten- 

 den, Studies in Physiological Chemistry, Yale University, 1889, iii, p. 100; 



