Contents

27 May 1988
Vol 240, Issue 4856

About The Cover

Adult brown wheat mite, Petrobia latens Muller (body size about 0.5 millimeter). This spider mite species transmits the causal agent of a unique virus-like disease of barley. Although the disease is currently known to be confined to Montana and contiguous areas in Canada, the mite is distributed throughout the world and therefore presents a threat to other barley-producing regions. See page 1188. [Nancy L. Robertson, Montana State University, Bozeman, MT 59717]