Galvanic skin response was observed in an absence of epidermis, in the existence of ingoing current flow and recorded simultaneously with impedance change. Conclusion was drawn that galvanic skin response recorded by endosomatic method is a summation of two processes: The negative process is caused by change of apparent skin resistance and the positive process is induced by electrical activity of sweat gland.
The variability of wave form with use of small electrode was recognized and a comparison of exosomatic and endosomatic method was made.

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Evidences were presented showing that the internodes of myelinated fibres respond to externally applied outward current.
The responses are characterized by high threshold and graded nature in size.
Similar responses can be evoked from the juxta-nodal myelin-covered portions of a fibre.
Evidences were presented showing that the inward internodal membrane current accompanying normal conduction is an expression of the internodal activity.
It was concluded that the internode is excitable, but whether it propagates and whether it excites the adjacent node or not, are unknown.

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1. The spike potentials were recorded intracellularly from spinal ganglion cells of toads and they were analysed by using the hyperpolarisation.
2. The intracellular action potential of the spinal ganglion cell had two inflections, which is attributed to successive initiation of three component spikes, the S, NM and M spikes.
3. The magnitude of the S spike and that of the second inflection increased with the increase of the membrane potential along lines having a slope of unity. This indicates that the S spike is generated from the cell body.
4. The magnitude of the NM spike as well as that of the first inflection showed a linear increase with the slope smaller than unity, by which the NM spike is attributed to the non-myelinated segment.
5. The critical depolarisation for initiating the NM spike was 15 mV, while that for initiating the S spike was 45 mV. This difference should be due to the membrane properties of the non-myelinated segment and the cell body.
6. The potential spread along the axon of the ganglion cell was estimated. The spike potential generated from the myelinated axon had an attenuation factor of 0.2-0.6 for its electrotonic spread to the non-myelinated segment and 0.3-0.8 for the further spread to the cell body. The spike potential generated from the non-myelinated segment spreads to the cell body by a factor larger than 0.5.
7. The hyperpolarised potential as well as the depolarised one spread electrotonically to the non-myelinated segment without suffering from attenuation. The former also extended to the site of the M spike generation decreasing by a factor of 0.5-1.0.
8. The critical hyperpolarisation for blocking the M-NM and NM-S conductions and their safety factors were estimated with suitable assumptions.

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1. The conduction of the impulse through toad spinal ganglion was studied by analysing the action potential obtained from the ganglion cells with an intracellular electrode and by recording the conducted spike potential from the peripheral nerve or from the dorsal root.
2. By making the cell hyperpolarised and refractory the site generating the M spike, the smallest component of the intracellular spikes, was confirmed to be nodes of Ranvier locating between the non-myelinated segment and the bifurcation and including the one at the bifurcation.
3. The conduction from the dorsal root to the bifurcation was blocked by a smaller hyperpolarisation than that from the peripheral nerve, and the least interval of the former was longer than that of the latter.
4. Urethane affected the centrifugal conduction through the spinal ganglion much more than the centripetal one, indicating that the conduction from the bifurcation to the dorsal root has a larger safety factor than that of the inverse direction.
5. Repetitive activation of the nerve affected the conduction from the bifurcation to the cell body more than that through the bifurcation from the peripheral nerve to the dorsal root. This was correlated with the development of the ganglion cell from a bipolar type in fishes to a monopolar one in higher vertebrates.

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On the dogs and cats decerebrated under urethane and morphine anesthesia the transection of the brain stem was performed to ascertain whether the socalled pneumotaxic center plays any role in originating a normal respiratory rhyhtm or not.
(1) The rostral half or two thirds of the pons could be removed without producing any remarkable change of the breathings, i.e., without producing the apneusis or apneustic breathings.
(2) From the results described above it may be unnecessary to assume the socalled pneumotaxic center to exist in the upper pons.

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With anesthetized dogs the intrinsic reflexes were studied in the denervated colon.
(1) The intrinsic reflexes consist of two different kinds of reflexes as in the small intestine; namely, one is elicited from the mucosa and the other from the muscular coats
(a) When the mucosal surface is stimulated mechanically (e.g., stroking) or chemically (e.g., HCl), the excitatory state is elicited on the oral side of the stimulated spot, giving rise to an increase in the strength of contraction waves, while the inhibitory state on the anal side, eliciting a decrease in the strength of contraction waves.
(b) When the muscular coats are stimulated mechanically or chemically, the inhibitory state is elicited on both sides of the stimulated spot, the effect being always stronger on the anal side than on the oral.
(2) The mucosal reflex is completely abolished after a large dose of hexamethonium bromide has been administered intravenously and locally, but the muscular reflex does not. As a consequence two reflexes appear to be essentially different from one another in their mechanism.
(3) From the results described above the causes of discrepancies among the results obtained by previous authors were discussed. The mechanism of the normal movements of the colon was also considered.

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1. Determination of free amino acids in the choroid of the toad's eye was carried out by means of circular buffered paper chromatographic technique. From the visual comparison of the spots, the relative abundance of amino acids in the choroid was glutamic acid≥alanine>serine>aspartic acid.
2. A microscopic observation has been made on the retinal pigment migration of the frog's eye by means of intraocular injection method. Injection with aspartate into the dark-adapted eye, evoked an extreme migration of the retinal pigment, despite the fact that it was placed in the dark. Injection with either glutamate or oxalacetate, exhibited a partial pigment migration. Injections with another substances used in this experiment, had no effect on the pigment migration in the dark. When the dark-adapted frog was exposed to light after the injection with either NH₄Cl or α-alanine, the pigment migration was not evoked.

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1. The origin of the so-called cone action potential (S-potential) was studied histologically on the retina of Cyprinus auratus. After insertion of a superfine micropipette filled with 10% potassium ferricyanide to a depth where the S-potential was maximal in amplitude, ferricyanide ions were injected electro-phoretically to make react with ferrous ions diffusing in from the retinal surface and produce a stain of Turnbull's blue around the tip of electrode.
2. Examination on serial sections of such materials led to the conclusion that the optimal depth for recording the S-potential is around the border of inner plexiform and inner nuclear layer, ranging from a distal half of the former to proximal half of the latter. The result was discussed in the con-nection with some earlier observations.
3. Impulse discharges were detectable only from a depth about 50μ more proximal to the origin of S-potentials. Histologically, this depth corresponded to the layer of the ganglion cells.

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1. Electrical activities of single motoneurons in excised toad's spinal cord were explored with intracellular microelectrodes.
2. On the oscilloscopic tracings, the initiation of spike potentials was classified into two types: an LR-type and an abrupt-type. It was shown that in the former spike potentials were initiated from the soma introduced by local response, while in the latter they were initiated from the initial segment of motor axon.
3. Single motoneurons were stimulated by exponentially rising currents applied directly with intracellular electrodes and the threshold depolarization was investigated as a function of the latent time. The threshold depolarization remained unchanged while the latent time was less than about 10 msec. Beyond this limit, it rose gradually with increase in the latent time, showing accommodation of the motoneuron to sustained depolarization. Accommodation was more prominent in the initial segment of motor axon than in so ma.
4. Hill's constant of accommodation λ was found ranging from 25.5 to 70 msec. in the initial segment.
5. The local response was often observed in soma separated from the spike, with stimulating currents rising slow enough.
6. Wedenski inhibition was proven to occur in the synaptic transmission to spinal motoneurons.
7. Accommodation and local response in motoneurons were explained referring to the ionic hypothesis of excitation.

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1. The nature of Svaetichin's cone action potential was investigated on Cyprinus auratus by means of spectrum scanning method.
2. Three types of spectral response were obtained, which might be designated as RG, RYB and L respectively, but the polarity of the present RG-type was opposite to that given by Svaetichin.
3. Illumination given onto a retinal region at a distance from the recordingsite still produced response of considerable amplitude. The response could not be attributed to the effect of scattered light, since the response decreased to a great extent after making a cut to disconnect the recording and the illuminated regions.
4. The spectral response pattern was found to be determined only by the position where recording was made and to be independent of which part of the retina was illuminated.
5. It was confirmed that the site producing intraretinal action potential (fish EIRG) was second or higher neurone and not receptor itself.
6. Based on the above result, a model of functional organization of the retina was presented and fully discussed.

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Orthodromically elicited unitary activity of the pyramidal tract cells which were identified by adequate stimulation of the medullary pyramid of cats were analysed by microelectrode techniques and following results were obtained:
I) A pyramidal tract cell in the pericruciate cortex was fired by single shock stimulation of a peripheral skin nerve.
II) Discharge of the cell could be divided into two types. i.e. an initial spike and late spike discharges.
III) Mode of discharge of the cell was not fixed but a cell with short latency at one time fired at another time with long latency under some experimental situations.
IV) Spike discharges of a pyramidal tract cell appeared coincidentally with negative phases of the surface evoked potential.
V) The shortest connection of a corticospinal fiber from the ventrolateral nuclei of the thalamus to the pyramidal tract cell was monosynaptic in nature.

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Experimental studies are made to clarify the role of carbonic anhydrase upon the bicarbonate excretion from salivary glands with special reference to excretory mechanism of ions. Animals are mainly dogs and partly rabbits which are administrated with pilocarpine to promote salivary excretion. Outline of results are as follows;
1) The bicarbonate excretion from parotid gland is depressed by administration of various carbonic anhydrase inhibitors, and the salivary pH is decreased while CO₂ partial pressure in saliva is increased. Among the inhibitors examined, Diamox is the most powerful, then comes thiophen-2-sulfonamide, and next are Na₂S, NaN₃, sulfanilamide and p-sulfonamide benzoic acid, while NaSCN exerts the minimum action. This order of inhibitory actions coincides with that of inhibitory effects upon blood carbonic anhydrase which was determined by the in vivo experiment.
2) The bicarbonate excretion in saliva differs among various salivary glands. Its excretion rates relative to rate of salivary flow from the gland examined are in the following order: parotid gland of dog>submaxillary gland of dog>parotid gland of rabbit>sublingual gland of dog. This order coincides with that of carbonic anhydrase contents in theses glands.
From these, it is concluded that the bicarbonate in saliva is produced in gland cells from metabolic CO₂ under the action of carbonic anhydrase.
By comparing the relative amount of carbonic anhydrase in these glands with their histological structures, the site of its production is suggested to be the striated part of gland duct.
3) The concentrations of Na⁺, Cl^- and HCO₃^- in parotid saliva as well as in submaxillary saliva increase as the rate of salivary flow is accelerated, and approach certain maximum levels respectively. The K⁺ concentration is maintained almost constant regardless of salivary flow except when the flowing rate is very low. The ionic concentrations in sublingual saliva of dog are all maintained approximately constant.
The total ionic concentrations in parotid and submaxillary saliva of dog and also in rabbit parotid saliva are hypotonic even at the maximum levels of concentrations, while that in sublingual saliva is approximately isotonic.
Among the ions in saliva, Na⁺ and Cl^- are the most dominating, HCO₃^- is the next and K⁺ and other ions are the least ones. Excretions of Cl^- and HCO₃^- vary considerably among various glands, while that of K⁺ does not differ so far. The concentration of Na⁺ depends upon the tonicity of saliva.
4) The regression lines of excretory rates of main ions referring to the rate of salivary flow are estimated from these data, and, by comparing the constants of regression lines (the intercept constants and the regression coefficients) of various glands with their histological structures, the excretory mechanism of ions from salivary glands were discussed.

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