Grobbelaar, Nathanael; Robbertse, P.J. (Petrus Johannes), 1932-
(Elsevier, 2012-05)
The presence of small knobs/nodules found on the adaxial leaflet surface of some
Encephalartos species was investigated in 134 cycad species of nine genera. The knobs,
referred to as collicles, were found to be the result ...