"Protoplasm of rhizopods and plant cells: a contribution to the theory of the cell" is a book written by the outstanding German biologist Max Schulze. In this work, the author examines in detail the protoplasm of rhizopods - unicellular organisms that play an important role in biology. Schulze also examines the protoplasm of plant cells and compares their structure and function. The book is a significant contribution to the study of the biological nature of the cell and protoplasm, their properties and processes occurring inside. Schulze considers the relationship between the structure of the cell and its functions, emphasizing the importance of protoplasm as the central component of living organisms. This book is recommended for biologists, scientists, students, and anyone interested in cell biology and molecular biology. It is an important source of information about the structure and functions of living organisms at the cellular level.