A polarization survey of Pleiades cluster members and nonmembers has been carried out together with a determination of interstellar reddening for cluster members. No correlations of stellar position angles of polarization with nebular filament directions could be found. The emergent picture incorporates data at optical, millimeter, and radio wavelengths. Light from the eastern part of the cluster passes through only uniform interstellar foreground material (VLsR ~ 7 km s-1 ), resulting in

more »

... nt values of p(V) = 0.27%, (} = 114°, E(B-V) = 0.03 mag, and p/E = 8. This region coincides with a 21 cm H r minimum. Light from the northwestern part passes through the foreground material in addition to a patchy intracluster cloud. Depolarization occurs due to different magnetic field directions in the two clouds. We find lower polarization and higher reddening than in the east, as well as a rotation of position angles. Our two-cloud model raises the p/E ratio from an observed value of 4 to a true value of 8. The northwestern region coincides with that of a 21 cm H r maximum and largest reported CH+ absorption with VLsR ~ 10 km s-1 • The high reddening of -0.30 mag and polarization -2% in much of the southwestern region coincides with the position of the molecular cloud detected by Cohen in CO.