The book "Studies in the Psychology of Sexuality, Volume 1: The Evolution of Naturalness; The Phenomenon of Sexual Periodicity; Autoerotics" by Havlock Ellis is the first volume of a series of studies devoted to the psychology of sex. In this book, the author considers such important topics as the evolution of naturalness, the phenomenon of sexual periodicity, and autoerotics. Havelock Ellis examines the relationship between biological, psychological, and sociocultural aspects of gender, offering the reader in-depth analysis and new approaches to understanding these phenomena. The author provides insights into the psychology of human sexuality, fitting into the context of his time. "Studies in the Psychology of Sexuality, Volume 1" helps the reader to better understand the complex aspects of gender and sexuality, expanding his knowledge and worldview. This book is considered an important contribution to the psychological literature and remains relevant to this day for understanding human nature.