What do we learn about the ladies in the missionary circle from their discussion of the Mruna tribe and the African Americans in Maycomb?

Scout's experience with the Missionary Society women is somewhat mixed. She observes the hypocrisy with which the women try to do good for a remote culture like the Mrunas, but neglect the needs and sufferings of the black community in their own town. Particularly disconcerting is the way the women discriminate freely against the blacks, complaining about "sulky darkies" and making ridiculous insinuations that black men, spurred on by the trial, will start coming into their beds. The women's provincialism comes out when they speak of the Mruna people - it is evident that they have no understanding of how another way of worship could be just as spiritually meaningful as the religion they have always known. They also refuse to believe that the blacks of Maycomb are Christians, although as shown in Chapter 12, they are clearly worshipping the same God.