Language: English with trilingual summary in English, German, and French
The taxonomic value of seed characters in studies of Cactaceae has been appreciated for many years but it was only with the advent of the scanning electron microscope in the 1970 that the diverse surface micromorphology of the seeds was fully revealed. In an extensive survey by Barthlott & Voit at the University of Heidelberg more than 900 taxa were examined. From their published summary paper and unpublished data, 26 usable characters are discussed here, with suggestions for the English terminology of the structures and character-states observed. Seed-descriptions using these characters are then given for representatives of nearly all the accepted and putative genera in subfamily Cactoideae, followed by SEM photographs of over 350 taxa. The volume concludes with a list of publications containing SEMs of cactus seeds, compiled at the Royal Botanic Gardens, Kew, and a combined index to taxa illustrated in these publications and the present one.