This volume serves as the fourth annual supplement to the Index Kewensis, addressing the critical need for an updated, comprehensive record of botanical nomenclature for seed-bearing plants. R. A. Davies compiles essential data regarding new and revised plant names at the family level and below, ensuring that researchers and botanists maintain access to the most current taxonomic classifications. The work functions as a vital extension of the original 1895 reference, maintaining the rigorous standards required for systematic botanical documentation.

Botanists and researchers regard this series as a foundational reference tool for tracking taxonomic shifts in plant nomenclature. The text is noted for its high level of technical density and its utility as a primary source for historical and contemporary botanical classification.