Crude extract of ovaries of Triturus pyrrhogaster was implanted into the testis of the adult male and observations were made on the histological differentiation of terminal crest at the apex of the testis. In the control animal pellets of a mixture of crystalline estrogenic substance and starch were grafted into the testis in a similar way as in the 1st group.
The implantation of ovarian extract brought about a striking suppression of development of seminal tubules in the terminal crest followed by the differentiation of oviform germ cells. These feminized germ cells appeared outside the seminal tubules and each of them was individually enveloped within the follicle cells derived from the walls of the seminal tubules. The modification of sex differentiation was observed not only in the terminal crests of the operated lobes but also in those which lie far from the site of implantation.
Crystalline sex hormone, on the other hand, exerted a severe destructive influence upon the germ cell differentiation in the testis but the differentiation of primordial seminal tubules was less conspicuously affected and oviform germ cell differentiation was detected only in a single specimen in which 2 cells accompanied by several small spermatogonia were formed in a common follicular tissue derived from the cells of the wall of seminal tubules.
These results, taken together with those of previous experiments, show that the ovary of T. pyrrhogaster produces an inductive substance which affects the sex differentiation of the terminal crest in a manner different from that of estrogenic hormones already known.

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Effect of some antidiabetics on the blood sugar curve after intravenous injection of glucose was investigated with the rabbits pre-treated with priscoline. Since an action of priscoline was found to make the curve type exponential, configuration of glucose tolerance curve could be determined by two constants, e^-k and C in a formula y_t=ae^-kt+C (y, blood sugar level; t, time; a, initial blood sugar).
Influences of antidiabetics, insulin, tolbutamide (N-toluyl-sulfonyl-N'-butylurea), metformin (Dimethylbiguanide) and sodium mesoxalate injected intravenously, were as follows:
(1)Examinations after single administrationa) After administration of 0.05u./kg of regular insulin, e^-k and C became both smaller than those for control. They were influenced in the similar way by subcutaneous injection of 0.1u./kg. b) After injection of 100mg/kg of tolbutamide, C value decreased significantly without change in e-k value. c) 50mg/kg of metformin gave an increasing effect on both of the two constants.
(2) Examinations after repeated administrationsAfter the administrations of 100mg/kg of sodium mesoxalate during 5 or 10 days, e^-k became smaller but Clarger.
(3) There were not any changes in e^-k and I values at ter single administration of 100mg/kg of the mesoxalate, or after the repeated administrations of 0.05u./kg of insulin, 100mg/kg of tolbutamide or 31mg/kg of the mesoxalate.
Mechanism of these actions was briefly referred to, and a possibility was discussed to apply this glucose tolerance test to the pharmacological screening method for antidiabetics.

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Thyroidectomy markedly inhibited the weight increase of the salivary glands, especially the submaxillary glands of rats and the simultaneous administration of thyroxine to the thyroidectomized animals could make the salivary glands to recover the normal control level. Nucleic acid in the submaxillary glands was markedly decreased by thyroidectomy and recovered to its normal value by administration of thyroxine. The inhibition of the weight increase of the salivary glands caused by administration of antithyroid drugs; methylmercaptoimidazole or methylthiouracil, was also prevented by thyroxine. The study made to know the mode of action of methylmercaptoimidazole suggested that this antithyroid drug has no direct action on the salivary glands.

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The investigation into the pathogenesis of 8 cases with hypophosphatemic vitamin D refractory rickets of the simple type or Phosphatdiabetes shows that this disease is divided at least 2 types which are produced and developed respectively through the distinct pathogenesis, namely the pathogenesis of causing secondary parathyroid hyperfunction owing to the lowering of serum calcium through the deficient absorption of calcium from the gastrointestinal tract and the pathogenesis of causing the defect in the renal tubular mechanism for the reabsorption of phosphate.

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A prolactin-like substance was isolated from the human placenta by the method of extraction with alkaline water of pH 8.6-8.8 and the fractional precipitation with ammonium sulfate. The substance possesses the crop-glandstimulating activity similar to the anterior pituitary lactogenic hormone. The activity is concentrated in a precipitate at the concentration of 10-25% of ammonium sulfate from the pH 5.4-precipitate. This fraction causes proliferation of the mucous membrane of the crop-gland, production of the crop milk and increase of the granules of the fat in the crop milk.

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When the fraction which precipitates at the concentration of 10-25% of ammonium sulfate from the pH 5.4-precipitate is dialyzed against water, a supernatant separated from the precipitate formed during dialysis increases the fatty granules in the crop milk and proliferation the mucous membrane of the cropglands of pigeons distinctly. Particularly, the number and size of the fatty granules in the crop milk of pigeons increase remarkably. On the purpose of the biological assay the successive injections for 4 days “local”-intradermally by over the crop-gland give good results.

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