[169] Mays: Untersuchungen aus d. physiol. Institute d. Universität Heidelberg, Band iii., p. 378; also Langley: On the Destruction of Ferments in the Alimentary Canal, Journal of Physiology, vol. iii., p. 263. In considering the general phenomena of proteolysis by trypsin, one is especially impressed by the large and rapid formation of peptone which almost invariably results from the action of a moderately strong solution of the ferment, on nearly every form of proteid matter. To be sure, primary products are first formed, but these are quickly converted into peptone, and a little experience in studying the action of pepsin and trypsin soon reveals the fact that the latter is especially a peptone-forming ferment. In other words, it is peculiarly adapted to take up the work where it has been left by pepsin and, if necessary, carry forward the hydrolytic change even to the extent of a conversion of the entire hemi-moiety into crystalline products. The primary products of trypsin-proteolysis, however, are not exactly identical with those formed by pepsin. Thus, protoproteoses and heteroproteoses seldom appear in an alkaline trypsin digestion; the proteid matter being in most cases, at least, directly converted into soluble deuteroproteoses,[170] which are then transformed by the further action of the ferment into peptones and other products. Hence, we may express the order of events in the trypsin digestion of a native proteid as follows: Native proteid. | Amphodeuteroproteoses. | Amphopeptones. ╱ ╲ ╱ ╲ Antipeptone. Hemipeptone. ╱ | ╲ ╱ | ╲ Leucin. Tyrosin. Aspartic acid, etc. [170] R. Neumeister: zur Kenntniss der Albumosen. Zeitschr. f. Biol. Band 23, p. 378. In the digestion of fresh blood-fibrin with trypsin, there is plainly a preliminary solution of the proteid without any marked transformation or cleavage occurring, the soluble product being apparently a globulin, coagulating at about 75° C.,[171] viz., at approximately the same temperature as serum-globulin. This body, however, quickly disappears, giving place to true deuteroproteoses as the ferment-action commences; for it is not probable that this globulin is a product of enzyme-action, but rather represents a simple solution of the fibrin by the alkaline fluid and salts. In any event, this globulin-like substance is not formed in the pancreatic digestion of coagulated-albumin, serum-albumin, or vitellin, and hence cannot be considered as a true product of trypsin-proteolysis. [171] Jac. G. Otto: Beiträge zur Kenntniss der Umwandlung von Eiweissstoffen durch Pancreas-ferment. Zeitschrift f. physiol. Chem., Band 8, p. 129.