416 Dentition as indicative of the Age 
Fig. 23. — Incisors of Calf at one montli. 
Fig. 24. — Molars of Calf at one montli. 
r 
the angle of the jaw increases as the fourth molar, which is the 
first permanent tooth, advances to occupy its place, as shown in 
Fig. 25. 
At the age of six months the fourth molar is well developed, 
but it is in close contact with the angle of the jaw, and the pos- 
terior surface is not quite free from the covering of the gum. 
Between six and twelve months old there are no important 
dental changes, the incisor teeth become worn, and as the jaws 
increase in size, there is more space left between them ; but it 
