Abstract
Anatomical features were studied and compared for 15 species of Calamus from South India: C. dransfieldii, C. nagbettai, C. thwaitesii, C. gamblei, C. hookerianus, C. karnatakensis, C. lacciferus, C. pseudotenuis, C. stoloniferus, C. vattayila, C. brandisii, C. lakshmanae, C. metzianus, C. rotang and C. travancoricus. The most promising features of diagnostic importance are epidermal cell size and shape and 'papilla'-like reflective bodies. While metaxylem vessel diameter, fibre wall thickness and stomatal frequency are often useful, fibre length and diameter, ground parenchyma, vessel perforations and silica bodies are of relatively little value in species separation. Although cell size often differs between the species of two different diameter classes, the majority of the anatomical features overlap among the species. Stem position is, however, an important part of anatomical variation. With the possible combination of several anatomical characteristics and stem diameter, a