ABSTRACT
Dr P. BAAS, professor emeritus of Systematic Botany in the University of Leiden. [Baa.]
Drs E.A.J. BURKE, lecturer, Institute for Earth Sciences of the Free University at Amster dam. [Bu.]
Dr B.C. DAMSTEEGT (ob.), professor emeritus of Dutch Philology in the University of Leiden. [Dam.]
Miss C. DIKSHOORN (ob.), English translator, at Zeist.
