In the present paper observations on the nest construction of the founding female of Polistes chinensis antennalis Perez just before or after the hatching period of the larvae were given. 1. Just before th e hatching of the larvae in the nest the founding female begins to preserve droplets of honey into the larval cells. So far as the author's observation goes, the external stimulus which initiates such behaviour seems to be the presence of the matured stage of the embryo within the egg. 2. Honey gathering activity of the founding female during the period just before the hatching of the larvae is more frequent in the forenoon than in the afternoon. On the other hand, the same activity seems to become more frequent in the afternoon than in the forenoon after the hatching of the larvae. 3. Between the nest construction activities the founding female takes another work or rests for a short time. Thus the nest construction behaviour is a remarkably rythmic one. 4. During this period such a distinct relation between the nest construction behaviour and the act of oviposition as reported in the author's previous paper cannot be observed in many cases. This phenomenon may be caused by the more complicated nest building activities. In other words, a new factor (newly hatched larvae) which stimulates the nest construction behaviour becomes to give some influences on the founding female. 5. Protection of the nest is a behav i our which is initiated by some external factors. Regulation of the nest temperature covers most of the times of this behaviour. Therefore, the daily change of the sequence of acts or behaviour has a close connection to that of the temperature of the nest environment. 6. After the hatching of the larvae the founding female may rest more frequently in the nest, and the time spent out of the nest for feeding or resting becomes extremely shorter. The most likely reason for this phenomenon is that the founding female can feed a part of food which should be shared to her brood on her nest even if she does not go out and, further, she becomes to remain on the nest for a long period owing to a physical influence which may be aroused by the appearance of the larvae in the nest. 7. The succession of daily behaviour of the fou n ding female is as follows: nest construction, food collection, resting and going out. The founding female repeats such a sequence of behaviour again and again. 8. Such behaviour as the collection of food, the supply of food and the protection of the nest (these are induced by some outer stimuli) is increasing gradualy just before or after the hatching of the larvae, while such acts as the nest construction, going out, oviposition, etc. (these are initiated by some inherent or internal stimuli) are inhibited or such a sequence of behaviour is apt to be interrupted markedly. Consequently, the behaviour system appears to become more complicated than before.