Whilst studying the material of the genus Securidaca for the “Flora of Suriname”, I found it in most cases extremely difficult or even impossible to identify the species. The original descriptions are, as a rule, very short, and they have been based for a good deal on incomplete material: mature fruits, for instance, are often missing. Hence it is not surprising that on quite a number of species the opinions of taxonomists disagree. Accordingly on the one hand we may find in the various collections the most different species lumped together under the same name, while on the other hand one and the same species may appear under several names. A study of the type specimens therefore, was obviously very desirable. I am indebted to the “VAN EEDEN FONDS” for enabling me to visit the Herbarium in Paris, where I could clear up some misunderstandings with regard to the Suriname species. This study includes all the Suriname specimens preserved in the Herbaria of Utrecht, Leiden, Kew, Brussels, Geneva and Berlin, together with the material collected outside Suriname and available in the Utrecht and Paris collections, and the British Guiana plants of the Kew Herbarium. To get an impression of the genus as a whole, several species not occurring in Suriname have been studied, but a thorough investigation was made of the Suriname ones only. The results of this investigation will be given below.