280 Microscopie Structure of Cortical Areas 
Fie. 7. Cortex from the motor area of the human brain. 
1. A. Layer of glia cells and outer layer of tangential fibers. 
2. B. Outer layer of polymorphous cells. 
3. C. Layer of parapyknomorphous pyramidal cells. 
4. D. Layer of large, or pyknomorphous pyramidal cells. 
E. Inner layer of polymorphous cells. 
Fic. 8. Cortex from the parietal lobe of the human brain. 
1. A. Layer of glia cells and outer layer of tangential fibers. 
2. B. Outer layer of polymorphous cells. 
38. C. Layer of parapyknomorphous pyramidal cells. 
4. D. Outer layer of pyknomorphous pyramidal cells. 
5. E. Layer of granule cells. 
6. F. Inner layer of pyknomorphous pyramidal cells. 
7. G. Inner layer of polymorphous cells. 
Fie. 9. Cortex from the parietal lobe of the monkey. 
1. A. Layer of glia cells and outer layer of tangential fibers. 
2. B. Outer layer of polymorphous cells. 
3. C. Layer of parapyknomorphous pyramidal cells. 
y. D. Outer layer of pyknomorphous pyramidal cells. 
5. E. Layer of granule cells. 
6. F. Inner layer of pyknomorphous pyramidal cells. 
7. G. Inner layer of polymorphous cells. 
Fic. 10. Cortex from the parietal lobe of the dog’s brain. 
1. A. Layer of glia cells and outer layer of tangential fibers. 
2. B. Outer layer of polymorphous cells. 
3. C. Layer of parapyknomorphous pyramidal cells. 
4. D. Outer layer of pyknomorphous pyramidal cells. 
5. E. Layer of granule cells. (Layer of small stellate cells, by 
Ramon y Cajal.) 
6. F. Inner layer of pyknomorphous pyramidal cells. 
7. G. Inner layer of polymorphous cells. 
Fie. 11. Showing the transition from the seven-layer type to the visual 
area or eight-layer type in the monkey. 
7. T.—Seven-layer type. 
8. T.—EHight-layer type, or visual region. 
The seven-layer type is as in Fig. 9. 
Kight-Layer Type. 
1. A. Layer of glia cells and outer layer of tangential fibers. 
2. B. Outer layer of polymorphous cells. 
3. C. Layer of parapyknomorphous pyramidal cells. 
4. D. Layer of granule cells, with fusiform or irregular cells 
seattered here and there. 
5. E. Inner layer of tangential fibers. (External stripe of 
Baillarger.) 
6. EF. Layer of granule cells. 
7. G. Inner layer of tangential fibers. (Inner stripe of 
Baillarger.) 
8. H. Inner layer of polymorphous cells. 
