THE ASTRONOMICAL JOURNAL    VOLUME 107, NUMBER 5, PAGE 1629            MAY 1994

                   GALAXY STRUCTURES IN THE HERCULES REGION

             MASSIMO TARENGHI, BIANCA GARILLI, AND DARIO MACCAGNI

               European Southern Observatory, Garching, Germany
        Electronic mail: mtarengh@eso.org, bianca,dario@ifetr.mi.cnr.it

                                   ABSTRACT

    
    216 redshifts have been obtained in a region of 981 sq deg south of
    the Hercules supercluster.  172 of these redshifts are of galaxies with
    mpg <= 15.1, 110 of which had no previous velocity measurement.  44 new
    redshifts are of galaxies fainter than mpg = 15.1.  With these new data
    we have been able to define a sample in a vast region (~1700 sq deg)
    around Hercules limited to mpg <= 15.1 with a velocity completeness of
    81.5%.  189 galaxies have been morphologically classified so that all
    galaxies in the sample with known velocity now also have known
    morphology.  The magnitude limited sample, including 556 galaxies, is
    then used to identify and describe galaxy structures in the region.  We
    find that the overdense volume is small, that its overall appearance is
    that of "a coral branch floating in a sea of nothing" and that early
    and late type galaxies define different structures.