Abstract
The numbering systems used by Júlio Henriques when specimens were prepared for distribution as donations or for determination from the Herbarium COI (Coimbra, Portugal) are addressed, with particular emphasis on the collections made by Adolfo Moller and Francisco Quintas on São Tomé and Príncipe in the 19th century. The conflicting numbers and label data that are found on these collections have been the source of considerable confusion in determining what constitute duplicates, and in many cases the type status of such collections. An understanding of the administrative methodology and numbering system used by Henriques is critical in taxonomic studies on the flora of São Tomé and Príncipe and adjacent areas, as the early collections inevitably included large numbers of type specimens. Previous work done by Arthur Exell to address the issue is analysed and explained, and examples are presented.