Malaysian plant collectors and collections being a Cyclopaedia of botanical exploration in Malaysia and a guide to the concerned literature up to the year 1950

As long ago as 1926-27, during my last two years at Utrecht University, when studying the taxonomy and distribution of the Malaysian Bignoniaceae (Thesis 1927), I felt the need for a reference work in localizing inadequately labelled specimens. Material collected in the 19th century, especially that of BLUME, KORTHALS, JUNGHUHN, ZIPELIUS,¹ MOTLEY, HORSFIELD, etc. bear scant notes. Either these collectors did not realize the future value of full data or their notes were not mounted on the sheets in the herbarium and were often subsequently lost. I have also observed a tendency in some authors of tropical plant species in that period to underrate the importance of the locality because of their belief that tropical plants occurred everywhere in the tropics, i.e. were ubiquitous in the plant-geographical sense. Sometimes the collectors were natives accompanying expeditions, who did not make notes, e.g. JAHERI, ACHMAD, etc. Hence, it is often very difficult to trace the exact origin of specimens. KORTHALS’S plants, for example, are mostly labelled merely: ‘Borneo’. This botanist, however, described the parts of Borneo in which he collected and an extensive printed record of his travels is in existence.