24 April 2007
Vol 2007, Issue 383

About The Cover

Cover image expansion

COVER This week's Focus Issue, published to complement the Science Special Issue on Germ Cells, contains an Editorial Guide as well as one Perspective on the migration of primordial germ cells and elimination of those that fail to migrate and one on poppy rejection of self-incompatible pollen. The image depicts a pollen tube. [Image: Christopher Bickel, AAAS]