BAKHUIZEN VAN DEN BRINK Jr, R.C., A synoptical key to the genera of the Rubiaceae of Thailand. Thai Forest Bull. (Bot.) 9 (1976) 15-55. Key of the bracketed type, often leading to flowers as well as fruits, with built-in descriptions of c. 6-12 lines; diagnostic characters are marked. Number of genera 68, incl. 3 introductions and 5 genera not recorded but possibly occurring in Thailand (mostly dependent on delimitation); Craib in 1932-34 has 71. Schumann’s system of 1891 is largely upheld, although no subdivision is here given, and some surprising changes in delimitation occur (e.g. in Keenania, Mycetia, Myrioneuron), which means that many new combinations must be floating around on herbarium sheets. Caution is in order where e.g. on p. 49 Mitragyna seems to have a new section Paradina with a supposedly basal placenta, or where Gardenia is authorized L. on p. 35 but authorized L. emend. Bakh.f. on p. 32. A comparison with Thonner’s keys reveals that Bakhuizen’s key works slower. His generic descriptions are true ’mines of information’ – mining requires a lot of backtracking before all characters can be compared. Desirable as it would be to extend a work like this to all Malesia, it would be better to abandon the Backer-way of keying, and instead describe all genera clearly, and prepare a multiple key as worked out by Leenhouts. Some synonyms are given (Notodontia yes, Quiducia and Symphyllarion no), nomina conservanda indicated, no references, no species. Several critical notes are added. — C.E. Ridsdale & M.J.