into the Miocene epoch. Assuming that these apes lived about 600,000 years before Pithecanthropus, namely, in the later half of the Miocene, and taking puberty at ten years of age, a high estimate, we get not less than 60,000 generations.
2. From Apes back to lowest Lemurs in the lowest Eocene. The date of Eocene being fixed at 3,000,000, we have about 2,100,000 years for this stage; assuming as much as five years for puberty, this results in 420,000 generations.
3. From Lemures to Prototheria. The earliest known mammalian remains come from the Rhætic, or top formation of the Triassic epoch; allowing for the Rhætic only 100,000 years, we have to add the whole of the Jurassic and Cretaceous, in all about 5,500,000 years. Assuming three years for a generation, we get 1,800,000 generations.
4. From Prototheria to something like the Theromorpha at the bottom of the Triassic
