Sūta said: Years should be known as having six seasons. To the five types of subjects, viz.: bipeds, quadrupeds, birds, reptiles and the stationary beings, there are five Ārtavas (seasonal changes). The flower is remembered as Kālārtava (seasonal change indicating particular period of time of trees. The state of being Ṛtu and Ārtava is recounted as Pitṛtva (the state of being Pitṛs).