1. There are about 70 semi-wild horses in Toimisaki, of which only three are males. They are usually seen on the open pasture situated on the ridge of the mountain during the summer (from April to September) for grazing and copulation. But during the winter (from October to March) they go down in the forests of the mountain side where they find their own home territories.
2. There are two peaks in the above-mentioned open pasture. The horses which frequent either of the two peaks are as a rule identical according to the location of their own home territories.
3. In their home territories most horses live alone, but some live together in groups, which consist of from two to six.
4. Their territories often overlap one another. Neighborhood relation is held among the horses which live in territories overlapping one another. The territory of a male covers those of several females. Accordingly a kind of community relation the center of which is a male seems to be held among these horses.
5. The shape of the territory traced by the movement of the occupant is sometimes zonal or lineal. A nomadic movement like a pendulum is observed in such a territory.

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Problem. The object of this experiment is to show that the results of electroshock convulsion tried on mice by DUNCAN has the same tendency as that of the electroshock without convulsion on cats in our experiment.
Procedure. The subjects are cats (about 1 month old). The apparatus is applied according to the second simplified method of Mr. ISHIBASHI and Mr. NAKAI.
Learning. Put to dishes at the intervals of three meters, four meters away from the start. This experiment was continued till the cats reached the prey in one dish by the shortest way.
Electroshock; In the preliminary experiment we measured voltage caused by electroshock without convulsion, we found tonic, clonic convulsion seen in DUNCAN in electroshock convulsion.
Experiment. I. When food is put in one dish, we try electroshock without convulsion at the interval as by that of DUNCAN. II. When the experiment is done by one dish then try one in another dish, we examine the results of each experiment of the shocks caused by electroshock without convulsion. The time interval is same as that of DUNCAN.
Results and summary. Table 2 shows the result of the experiment I. Table 3 shows the result of experiment II.
1. We found the electroshock without convulsion in the cats three or five volt., after one minute.
2. We found temporary retrograde amnesia in the electroshock without convulsion.
3. Our result seems to be related with temporary retrograde amnesia in this case.

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Der Käfer stürzt sich sowohl auf den bei ihm schwebenden Koder wie auf irgend ein daran nahe liegendes Objekt; im Grund reagiert der vomKôder chemisch gereizte Käfer positiv vibrotaktisch auf die Wasserwellen, die aus dem Koder od. aus dem betreffenden Objekt kommen. Auf chemische Reize vom eingetatchten koder reagiert er mit dem Kreisschwimmen, aber nicht tropo-od. klino-taktisch.

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In this study, the reaction latency in rats was observed with an elevated straight run way. It was measured during the acquisition and the extinction period, and both results were compared. The rats here used were 21 white rats and 6 pigment rats, and the differences between two groups were compared, too.
Generally speaking, the latency in the acquision period and that in the extinction period did not show the mere inverse relation, and they were different qualitatively. Further, it seemed that there was a some inverse relation between the latency and the reaction potential (or excitatory tendency), but was not always a continuous smooth function like an exponential function. It was a noncontinuous relation, and it was assumed that there was a possibility of some complicated cognitive mechanisms.
As to the individual rats, in spite of the same experimental conditions, there were significant differences between the latency of white rats and that of pigment rats. Therefore, it could be inferred that some factors based on the hereditary and constitutional differences played a considerable role in these processes. Moreover, the measured values of individual rats showed great deviations, particularly in the extinction period.
However, since each rat showed some constant tendencies, it might be possible to adopt them as indexes of the individual differences.

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The aim of this study was to get an evidence of latent learning. 49 naive albino rats ran in the T-maze. The right arm and goal box of it.was painted light gray, and the left arm and goal box was painted black.The choice point and the stem of it was also painted neutral gray. Further, wood-shavings were put in the right goal box.
4 trials were given per day for 6 days, and the half of these were to the right and the other half were to the left. In all training period, food was introduced in the both goal boxes.
After this training, food was removed from the goal boxes, and each rat was put and confined in one empty goal box, which was preferred in the training period. This procedure was called “extinction.” After this, one test trial was given
.The results obtained were as follows.
(1) When the extinction was done in another room with another boxes of the same size and color as the goal boxes of the maze, the result was negative to the latent learning. (Exp.I)
(2) When the extinction was done in the goal box of the maze for three minutes and the test was given immediately after it, the result was positive. (Exp. II)
(3) When the extinction was done for two minutes and this was repeated two times with the interval of about 15 minutes, and the test was given after about 15 minutes, the result was positive. (Exp. III)
(4) When the rats ran to the goal box by themselves and were confined there for three minutes, the result of the test after 10 minutes was almost the same as the mentioned above (Exp. IV). This was the control experiment.
According to these results, we concluded that our experiments clearly demonstrated the latent learning.

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The author studied the visual acuity of loath, Misgurnus anguillicaudatus by means of training for striped patterns. All the experiments were performed in a dark room, under uniformly diffused illumination of 160 lux. The fish (body length 4-5 cm) was separately introduced into a glass dish of 15 cm diameter, containing water 4 cm in depth.One half of the dish was underlaid by a grey paper of series Nr. 1 (white) Nr.10 (black), while another half by a paper, on which stripes, i. e. white and black lines (both 3, 1, 0.5, 0.3, or 0.2 mm wide) ran perpendicularly to the grey-pattern boundary. The fish was supplied with food (Chironomus larvae), whenever it appeared on the pattern side. Everyday the fish was tested before beginning of training, i. e. we measured how long it stayed on the pattern side within a given period and thus calculated its rate of response. As the fish swum always immediately on the bottom, the rate of response would reasonably denote ability of fish to discriminate two line a given interval.
1. According to our previous study, the loach shows often negative phototaxis, so that it must be tested at first, whether training is prevented by the tendency to prefer darkness to brightness. In fact, the fish is able to be trained for white (Nr.1) against black (Nr.10) and vice versa, with equally good success.
2. The fish is easily trained for stripes 3 and 1 mm wide. The rate of response is always over 75% after 4-7 days. The loach can clearly distinguish 3 or 1 mm-striped pattern from every grade of grey series.
3. As for 0.2 mm-striped pattern, the rate of response is about 50 %. Though the fish can be trained with success to distinguish this pattern from a certain grey, it responds no longer to the pattern if the grey is exchanged for the darker (or lighter) one. Thus it is obvious that the loach looks 0.2 mm-striped pattern as an uniform grey.
4. It is not always clear whether the fish is able to discriminate 0.5 and 0.3 mm-striped pattern from grey series. Therefore, the limit of visual acuity (minimum separable) of loach is considered to be about 0.3-0.5 mm under conditions of our experiments.

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[in Japanese]

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