In any active pancreatic digestion of either a native proteid, or of the products of pepsin-proteolysis, the anti-group is represented mainly by antipeptone, although there is often found a small amount of a peculiar antialbumid-like body, insoluble in the weak alkaline fluid. Antipeptones, thus far studied, when entirely free from proteoses, are characterized by a low content of carbon, like the amphopeptones from pepsin-proteolysis. The following table shows the composition of a few typical examples: COMPOSITION OF ANTIPEPTONES. From From From blood- blood- anti- From From fibrin. fibrin. albumose. casein. myosin. [172] [173] [174] [175] [176] C 47.30 49.59 48.94 49.94 49.26 H 6.73 6.92 6.65 6.51 6.87 N 16.83 15.79 15.89 16.30 16.62 S 0.73 --- --- 0.68 1.16 O 28.41 --- --- 26.57 26.09 [172] Kühne and Chittenden: Studies in Physiol. Chem. Yale Univer., vol. ii., p. 40. [173] J. Otto: Zeitschr. f. physiol. Chem., Band 8, p. 146. [174] Kühne and Chittenden: Zeitschr. f. Biol., Band 19, p. 196. [175] Chittenden: Studies in Physiol. Chem. Yale Univer., vol. iii., p. 101. [176] Chittenden and Goodwin: Journal of Physiol., vol. xii., p. 34. From these data it is evident that, while each individual peptone may have a composition peculiar to itself, they are all alike in possessing a relatively low content of carbon. The antialbumid, however, split off in these hydrolytic changes, like the antialbumid formed by the action of dilute acids at 100° C., is characterized by a correspondingly high content of carbon and a low content of nitrogen. As an illustration, may be mentioned the myosin-antialbumid formed in the digestion of myosin from muscle-tissue by an alkaline trypsin-solution. This body contains 57.48 per cent. of carbon, 7.67 per cent. of hydrogen, 13.94 per cent. of nitrogen, 1.32 per cent. of sulphur, and 19.59 per cent. of oxygen.[177] It is only necessary to compare these figures with those expressive of the composition of myosin-antipeptone, to appreciate how wide a gap there is between these two products of trypsin-proteolysis, and both members of the anti-group. Antialbumid, however, is a peculiar product, one which is liable to crop out somewhat unexpectedly, and with varying shades of resistance toward the proteolytic ferments. As formed in pepsin-proteolysis, it is more or less readily soluble in sodium carbonate, and in part readily convertible into antipeptone by trypsin. Still, the same substance, or at least a closely related body, makes its appearance in the form of an insoluble residue whenever a native proteid is digested by trypsin. At times, the amount of this insoluble product may be quite large,