No. 1, August, 1921] PHYSIOLOGY 75 



amines (cholin, etc.), neurin group, diamines (lysin, etc.), guanidin compounds, imidazole 

 (histidin), betaines and a-amino acids, the phcnylalkyl- and phcnylalkanolamines (ephedrin, 

 adrenalin, etc.), and indole thylamine. Under each substance there is a brief account of its 

 discovery, occurrence and origin, composition, methods of preparation, and, so far as possible, 

 its biological significance. The author regards the further study of these bodies as most 

 important, offering such possibilities as rational explanations of vitamines, increased light 

 on phenomena of virulence and immunity, and rapidly advancing knowledge in the field of 

 internal secretions. — B. M. Duggar. 



502. IMannich, C, und G. Wipperling. Die Trennung und quantitative Bestimraung 

 von Protein und Nichtprotein-Stickstoflf durch Ultrafiltration. [Separation and quantitative 

 determination of protein and non-protein nitrogen by ultrafiltration.] Zeitschr. Untersuch. 

 Nahrungs- u. Geuussmittel 40: 12-20. 1920. — Beans, hops, carrots, potatoes, cottonseed, and 

 wheat were analyzed. While the results varied considerably from parallel determinations 

 by the accepted method, it is claimed that ultrafiltration will prove useful. — H. G. Barbour. 



503. Strowd, W. H. The forms of nitrogen in soy-bean nodules. Soil Sci. 11: 123-130. 

 1921. — An examination of 100 gr. of soybean nodules failed to show the cyanide radical 

 by a method sensitive to 0.01 mg. of hydrocyanic acid. Of the total nitrogen in nodules 30- 

 40 per cent is water-soluble and 40-55 per cent soluble in 10 per cent salt or dilute alkali. 

 About 3 per cent of the water-soluble nitrogen was protein or proteose.* No globulin and only 

 a small amount of albumin was found. Primary amino nitrogen formed 16 per cent of the pro- 

 tein-free water-soluble nitrogen, and amide nitrogen 19.3 per cent. Over 60 per cent of the 

 total water-soluble nitrogen was precipitated by phospho-tungstic acid.^lF. J. Robbins. 



504. WooDARD, J. Tyrosin in fungi. [Rev. of: Dodge, C. W. Tyrosin in the fungi: 

 chemistry and methods of studying the tyrosinase reaction. Ann. Missouri Bot. Gard. 6: 

 71-92. 1919 (see Bot. Absts. 4, fcntry 1446).] Bot. Gaz. 69: 191. 1920. 



METABOLISM (ENZYMES, FERMENTATION) 



505. Anonymous. [Rev. of: Effront, Jean. Biochemical catalysts in life and industry. 

 Proteolytic enzymes, xii + 752 p. John Wiley & Sons: New York; Chapman & Hall: 

 London, 1917.] Sci. Prog. [London] 14: 347-348. 1919. 



506. Bridel, M., et R. Arnold. Bur I'emploi de divers agents de precipitation dans la 

 preparation de I'emulsine des amandes. [The use of different precipitation agents in the prep- 

 aration of the emulsin of almonds.] Jour. Pharm. et Chimie 23: 161-168. 1921. — Emulsin 

 of almonds is generally prepared by H^rissey's process, that is, macerating the almonds with 

 water, removing the casein by means of acetic acid, and precipitating the ferment by strong 

 alcohol. Thus a mixture of ferments is obtained which consists of emulsin proper or /3 glu- 

 cosidase, lactase, gentiobiase, cellobiase, melibiase, manninobiase, /3 galactosides, and a 

 small amount of invertin. When alcohol is replaced by methyl alcohol or acetone and when 

 too long a contact of the precipitant with the ferments is avoided, a ferment is obtained which 

 possesses practically all the properties of ordinary emulsin. Furthermore, when the ferment 

 is allowed to remain in contact with the precipitation liquid for too long a time an emulsin 

 is obtained which is devoid of certain other ferments. — H. Engelhardt. 



507. Harter, L. L. Amylase of Rhizopus tritici, with a consideration of its secretion and 

 action. Jour. Agric. Res. 20: 761-786. 1921. — A vigorous starch-splitting enzyme is secreted by 

 R. tritici. The enzyme from old mycelium is less active than that from young. Storage of the 

 dried mycelium for several months at from 9° to 35°C. does not lessen its power of digestion, 

 but at 60° it becomes gradually less. The optimum temperature for the digestion of starch is 

 about 45°C. The hydrolytic capacity is destroyed in 100 hours at 60°C. Glucose retards the 

 hydrolysis of starch paste, although the quantity of glucose does not influence the results. 

 With a constant amount of enzyme powder hydrolysis increases with the increase in volume 



