This eighth volume in a series begun by Dr. J. LeRoy Conel in 1939 extends his investigation of the human cerebral cortex to the six-year stage of development. As in the preceding volumes, several features of the microscopic structure of the cortex are described in great detail. In a concluding commentary, the author summarizes his findings and provides comparisons between the six-year and the four-year stages of development. Well-known to specialists, this important series of books lays a uniquely valuable foundation for further neurological research.