The result of my experiments (VIII) on the relation between the crowing and the weather at the sunrise can be summarized as bellow :
1. The crowing is influenced by the weather condition. The cocks are fairly sensitive to the change of weather.
2. If fine weather continues, the impulse to crownig is augmented and the cocks crow oftener and oftener. On the contrary, if sky is covered after continuous cloudy, rainy or stormy weather, the cocks crow less often.
3. Temperature of atmospheric pressure has nothing to do with the frequency of crowing. The latter is determined dy the luminosity of the daylight.
4. Fine or rain the cocks held in separation crow always oftener than those held in cohabitation.
5. If we transfer the cocks from the state of separation to that of cohabitation or vice versa the frequency of crowing is diminished or augmented accordingly. Although the frequency is thus determined by the stumulus of testicular hormones, it is, nevertheless, true, that the small variation in the frequency is caused by the state of weather.
6. About one third of the entire crowing is accomplished at the sunrise.
7. The cocks crow often at the dawn, because their energy for crowing has been accumulated during the sleep. The minute fluctuation in the frequency of crowing towards daybreak is caused by the state of weather, which is not exactly alike all days.

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