Contents

31 July 1987
Vol 237, Issue 4814

About The Cover

Lithograph depicting seed (center) and other parts of Cycas circinalis Linn. (false sago palm), a neurotoxic plant. Heavy use of cycad seed for food and medicine has been linked to Guam amyotrophic lateral sclerosis and parkinsonismdementia, a prototypical disease for study of neurodegenerative disorders of old age. Now considered rare and endangered, cycads are primitive “gymnosperms” that flourished 150 to 200 million years ago. See page 517. [Figure 176C in C. L. Blume, Commentationes Botanicae. Imprime de Plantis Indae Orientalis. Rumphia (Lugduni-Batavorum, Amsterdam, 1848), Part IV, pages 11-18]