Contents

09 June 1995
Vol 268, Issue 5216

About The Cover

The crustose lichen Lecanora dispersa. Lichen symbioses, associations between fungi and algae, have originated multiple times during fungal evolution. At least one successful establishment of symbiosis led to the more than 6000 species of the order Lecanorales, represented here by L. dispersa. The white-rimmed cups (between 0.3 and 0.7 millimeter in diameter) emerging from the rock substrate produce the meiotic spores of this fungal symbiont. See page 1492 and the News story on page 1437. [Photo: V. Wirth]