A new micro-method for quantitatve determination of cholic and desocycholic acid in bile is reported and some analytical examples are given.
The author is greatly indebtedto Prof. K. Kodama and Prof. S. Akaiwa for their kind suggestion and criticism.

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Eine lichtelektrische spektrophotometrische Methode mittels Photozellen and Vakuum-Verstärkersystems wird beschrieben, mit welcher die Extinktionskoefficienten der gelösten Substanzen in jedem Wellenlängenbezirke zwischen 190 his 730 mμ genau bestimmbar sind. Die dazu notwendige Technik, Vorsichts-massregeln and einige 11lessergebnisse werden mitgeteilt.

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1. The redox-potential of normal frog muscle is nearly -! 230 mv. Eli.
2. Irradiation with ultraviolet- or Röntgen-rays causes the increase of the reduction-potential, which is highest at the dosage of 10 minutes exposure with ultraviolet-rays and at 135r with Rontgen-rays. At larger dosages this increase was rather inhibited.
3. With ultraviolet-rays the rise of the reduction-potential took place soon after the irradiation, but with Röntgen-rays it happened after certain intervals.
4. The above observed change of the potential took place only when each components of the reducing system in muscle (Dehydro-genase+H₂-donator) are all present.
5. The recovery of the potential to the initial value took place earlier in the case of ultraviolet-rays than in the case of Rontgen-rays.
6. There exists an optimal dosage of irradiation for the in-crease of the reduced glutathlone. By applying excess it was rather inhibited.
7. It is proposed that the biological effect of light might be partially sought in the activation of the reducing agents in the tissue.
The author is deeply indebted to Prof. Dr. K. K o d a in a for his kind direction and criticism and to Prof. Al. Shiraki for his kind encouragement throughout this work.

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1. A new direct titration method is described in detail.
2. The heating is effected by the current of steam, which avoids the overheating and retains the volume of reacting mixture within a certain range. These conditions afford us always the constant titration values for the sugar solution of 0.20-1.0gm/dl concentration.
3. The preparation of the reagent is easy and the cost is far reduced compared with the Benedict's reagent.
4. The reagent is highly durable.
5. The manipulations of this new titration method seem to be far easier than that of Benedict's once the current of steam has been regulated.

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β-Naphtholgluvcuronic acid was not detected in urine of naphthalenized rabbits. α-naphtholglucuronic acid was isolated, tut merely in one trial of preparation and in al others, which succeeded (the third method) a new compound, α-naphthol-penturonic acid hydrate.
Ther writer owes the elementar analyses to Dr. S. Umezawa, Assistant of Professor H. Suginome in the Chemical Institute.

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1) In der vorliegenden Arbeit habe ich das Verhalten der durch den Pankreassaft des Kaninchens sowie die Magenschleimhaut des Schweins erzeugten Spaltungsendprodukte des Caseins (Hammersten) der Enzymwirkuug verschiedener Herkunft studiert.
Das hier untersuchte sogennante Trypsinpepton, das ich als “Trypton” bezeichnen möchte, verhält sich verschiedenen Fällungsreagentien gegenüber fast gleich wie das Pepton (Spaltungsendprodukt des Caseins durch Magenschleimhaut bei PH 2.0).
2) Das Pepton wurde weiter durch den aktivierten Pankreassaft angegriffen, während die Tryptonlösung der weiteren Wirkung der Magenschleimhaut sowie des Pankreassaftes hartnäckig widerstand.
3) Der Pankreasmazerationssaft des Kaninchens griff trotzdem die Trypton wie auch die Peptonlösung an. Bei dieser Wirkung dürfte es sich um die Gewebspeptidase handeln.
4) Trypton- und auch Peptonlösung wurde ferner durch Niere, Leber und Dünndarmschleimhaut bei schwach alkalischer Reaktion angegriffen. Diese hydrolysierende Wirkung der Niere wurde auch deutlich bei schwach saurer Reaktion (PH 4.5) beobachtet.
5) Bei den Versuchen mit verschiedenen PH-Werten fand sich der Optimalbereich für Gewebspeptonase für Niere und Leber bei PH 6.0-8.0.

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1. The reducing capacities of methylated glueoses (2-mono-methyl, 3-monomethyl, 6-monomethyl, 2.3-dimethyl, 2.3.4-trimethyl, 3.5.6-trimethyl, 2.3.5.6-tetramethyl, 2.3.4.5-tetramethyl and 2.3.4.5.6-pentamethyl glucose) were determined by the procedures of Hanes, Somogyi, and Jonesco-Matinet and Vitner. Sobotka's observation with reference to the relation between reducing power and the position or number of methyl groups was confirmed for the most part.
2. The finer influence of the position and number of methyl groups on the facility of enolization and thus oxidation of the methylated glucoses was examined under milder conditions than those of the ordinary procedures of sugar determination. It was demonstrated with the Hanes procedure at 70°C. and with the potentiometric determination in the medium of alkaline ferricy-anide, that the oxidation of 3-monomethyl glucose and 3.5.6-trimethyl glucose, took place with higher initial velocities but later the velocities diminished more rapidly than those in the case of the oxidation of unsubstituted glucose. In comparing the velocities of oxidation of 2.3.4.6-tetramethyl glucose and 2-monomethyl glucose a similar relation was observed.
3. 3-Monomethyl glucose decolorized inethylene blue in Thunberg's tube with considerably greater velocity than free glucose.
4. The Lobry de Bruyn-van Ekenstein transformation of 3-monomethyl glucose took place more easily than that of un-substituted glucose. In the transformation of 2-monomethyl glucose, interconversion of glucose to mannose only took place, no ketose being formed.
5. The production of formaldehyde from methylated sugars was examined by oxidizing with periodic acid. The yield of formaldehyde seemed to decrease with the proximity of methyl group to C₆ and with the increase of the number of the groups.
6. The quasi-equilibrium-potentials of methylated sugars were observed. The potential of n-tetramethyl glucose showed a rapid fall of about 100 millivolts in alkaline medium.

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