MR. W. K. PARKER ON THE STRUCTURE AND DEVELOPMENT 
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Fig. 4. The same from below (not straightened). X 16 diameters. 
Fig. 5. The same from above. X 16 diameters. 
Fig. 6. Palatal view of severed head of same. X 16 diameters. 
PLATE 28. 
Fig. 1. Third stage. Side view of the head of an Embryo, If inch long. X 8 
diameters. 
Fig. 2. The same dissected. X 8 diameters. 
Fig. 3. The same from above. X 8 diameters. 
Fig. 4. The same ; palatal view, with lower arches removed. X 8 diameters. 
Fig. 5. Longitudinally vertical section of the same. X 12 diameters. 
Fig. 6. Palatal view of same dissected. X 12 diameters. 
Fig. 7. Ear-capsule and arches of same, side view. X 12 diameters. 
Fig. 8. Upper view of chondrocranium of an older Embryo, measuring 2f inches long. 
X 12 diameters. 
Fig. 9. Nasal capsule of same, front view. X 12 diameters. 
PLATE 29. 
Fig. 1. First stage. Vertical section of head of youngest Embryo, f inch long. 
X 17 diameters. 
Fig. 2. Second stage. Vertical section of head of Embryo, 1 inch long. X 12 
diameters. 
Fig. 3. Fourth stage, 2f to 3 inches long. Side view of skull with nasal sac removed 
to show septum nasi. X 15 diameters. 
Fig. 4. Upper view of a skull of a somewhat older Embryo with all the sense- capsules 
in situ. X 12 diameters. 
Fig. 5. Lower view of chondrocranium (same as fig. 3), with eyeballs and nasal sacs 
not drawn. X 12 diameters. 
PLATE 30. 
Fig. 1. Longitudinally vertical section of a skull — (fourth stage continued). 
X 12 diameters. 
Fig. 2. Transversely vertical section of a similar skull through the middle of the nasal 
region. X 16 diameters. 
Fig. 3. A second section through fore part of eyeballs. X 16 diameters. 
Fig. 4. Part of a third section through the middle of the eyeballs. X 16 diameters. 
Fig. 5. A fourth section between eye and ear. X 16 diameters. 
Fig. 6. A fifth section through fore part of ear-capsules. X 16 diameters. 
Fief. 7. A sixth section through their middle. X 16 diameters. 
Fig. S. A seventh section between ear-capsules and foramen magnum. X 16 diameters. 
