| Abstract | The spiral arm classes of 762 galaxies are tabulated; 636 galaxies with low inclinations and radii larger than 1 arcmin were classified on the basis of their blue images on the Palomar Observatory Sky Survey (POSS), 76 SA galaxies in the group catalog of Geller and Huchra were also classified from the POSS, and 253 galaxies in high-resolution atlases were classified from their atlas photographs. This spiral arm classification system was previously shown to correlate with the presence of density waves, and galaxies with such waves were shown to occur primarily in the densest galactic groups. The present sample indicates, in addition, that grand design galaxies (i.e., those which tend to contain prominent density wave modes) are physically larger than flocculent galaxies (which do not contain such prominent modes) by a factor of about 1.5. A larger group sample confirms the previous result that grand design galaxies are preferentially in dense groups. |
