Please note, as far as I understand, this is not actually neither in Darwin's books nor printed at that time, this is just a later interpretation by people who read Darwin and wanted to use it for their own purposes. I wrote 1871 because that is the closest I can come for a text that would be the basis for these racist caricatures.

This is one of the justifications of colonisation, and particularly one of the pillars of 'fatal impact theory'.

The primitive 'man' is barely differentiated from an animal, especially when compared to a civilized 'man' (white, Christian).

Found the image with higher resolution:

via