Cross-cultural and cross-species developmental data are examined with the goal of defining tentatively the process of psychosexual development that might be considered species-specific for Homo sapiens. In comparison with this speculative norm, it is hypothesized that much of what is regarded as normal adolescent sexuality in the United States middle class represents psychologically delayed childhood. The pathogenic implications are discussed with respect to the expectable consequences of emotional development that must take place significantly past its critical or optimal period, and research possibilities are suggested.