Abstract

The presence of two different types of fibres in the wood of the subfamily Phyllanthoideae (Euphorbiaceae) is recorded: type I in which the fibres have moderately thick walls, a clearly defined lumen cavity and a normal birefringence pattern, and type I1 in which the walls are very thick, have no lumen cavity and a birefringence pattern suggesting an absence of an S₃ layer. The genera fall into three groups: those containing type I only, those with type II only, and those with both type I and type II. The fibre type in this family appears to be of taxonomic significance.