Fœtal: 1st month, that of an avertebrated animal;
Scale: Vertebrata Pisces (32, 33, 34, 35, 36)
Order: True Fishes
Rocks: 5. Carboniferous formation
Fœtal: 2nd month, that of a fish;
Scale: Vertebrata Reptilia (37, 38, 39, 40)
Order: Piscine Saurians (ichthyosaurus, &c.), Pterodactyles, Crocodiles, Tortoises, Batrachians
Rocks: 6. New Red Sandstone
Fœtal: 3rd month, that of a turtle;
Scale: Vertebrata Aves (41, 42, 43, 44, 45, 46)