Contents

12 July 1991
Vol 253, Issue 5016

About The Cover

The parasitic ciliate Lambornella clarki, flanked by free-living protozoa and surrounded by larvae and pupae of its mosquito host, Aedes sierrensis. The impact of fatal L. clarki infections on host populations in treeholes varies with food availability and can result in greater host abundance and fecundity when resources are scarce. See page 185. [Illustration by Jan O. Washburn; color tinting by Julie Cherry]