A first suggestion as to chromatic coding in the visual pathway of primates was that the six layers of the lateral geniculate nucleus (LGN) was devoted to different cone types, one per eye per cone (Le Gros Clark, 1949); recent work on koniocellular laminae has suggested this principle is not so outlandish. From a current perspective, early physiological studies were technically primitive, and led to some misleading conclusions, such as the presence of a substantial proportion of achromatic neurons in the parvocellular layers. Another misleading path was the attempt to push the visual system of the primate (and other species) into a framework set by work on the cat retina and LGN. It is now established that primates are the only mammals to have evolved full trichromatic vision and there is cumulative evidence that the primate visual pathway has been heavily modified to accommodate trichromacy, whatever the phylogenetic origins. The development of views of the primate visual pathway will be reviewed, and some frequent assumptions, deriving from those earlier studies, challenged.