A catalogue of galaxies behind the southern Milky Way

In this second paper of the catalogue series of galaxies behind the southern Milky Way, we report on the deep optical galaxy search in the Crux region ($289{^\circ}\le \ell \le 318{^\circ}$ and $-10{^\circ}\le b \le 10{^\circ}$) and the Great Attractor region ($316{^\circ}\le \ell \le 338{^\circ}$ and $-10{^\circ}\le b \le 10{^\circ}$). The galaxy catalogues are presented, a brief description of the galaxy search given, as well as a discussion on the distribution and characteristics of the uncovered galaxies. A total of 8182 galaxies with major diameters $D \gtrsim 0.\mkern-4mu^\prime2$ were identified in this ~850 square degree area: 3759 galaxies in the Crux region and 4423 galaxies in the Great Attractor region. Of the 8182 galaxies, 229 (2.8% ) were catalogued before in the optical (3 in radio) and 251 galaxies have a reliable (159), or likely (92) cross-identification in the IRAS Point Source Catalogue (3.1% ). A number of prominent overdensities and filaments of galaxies are identified. They are not correlated with the Galactic foreground extinction and hence indicative of extragalactic large-scale structures. Redshifts obtained at the South African Astronomical Observatory (SAAO) for 518 of the newly catalogued galaxies in the Crux and Great Attractor regions (Fairall et al. [CITE]; Woudt et al. [CITE]) confirm distinct voids and clusters in the area here surveyed. With this optical galaxy search, we have reduced the width of the optical "Zone of Avoidance" for galaxies with extinction-corrected diameters larger than 1.3 arcmin from extinction levels $A_B \ge 1.\!\!^{\rm m}0$ to $A_B \ge 3.\!\!^{\rm m}0$: the remaining optical Zone of Avoidance is now limited by $| b | \lesssim 3^\circ$ (see Fig. 16)