This issue is the first to be produced in offset print. 

 This constitutes part of our efforts to reduce the cost 

 of production. 



Edited by Dr.J.Faber, 



Deputy Director of the Hubrecht Laboratory 



Managing Editor: B.Z.Salome 



Hubrecht Laboratory 

 Uppsalalaan 1 , 



Universiteitscentrum "De Uithof 

 UTRECHT, Netherlands 



Printed in the Netherlands, 1972 



