A Survey of the Pisces-Perseus Supercluster. VI. The Declination Zone +15.5 degrees to n+21.5 degrees

New results are presented of Arecibo observations in the 21 cm line of 765 galaxies with declinations between 15.5^deg^ and 21.5^deg^, in the Pisces-Perseus supercluster zone. If considered independently on the neighboring parts of sky, this region, to the South of the supercluster ridge, shows significantly less evidence of structure on large scales in excess of 30 Mpc, contrasting substantially with the characteristics of the declination zones immediately to the North.