 The authors studied the \"logic\" of retinal projections to the SC according to the collicular output pathways. They used transsynaptic labeling to trace the RGCs that innervate the SC neurons projecting to the LP or the Pbg, then characterized the morphology and physiology of the labeled RGCs. Their results suggest a \"projection-specific\" logic. They also performed in vivo recording of the LP and the Pbg to correlate the response properties of these structures with those of the RGCs that target them di-synaptically. Overall, the topic is important, and the experiments/analysis are largely appropriate. But the authors tend to over-state their findings from a limited dataset. A number of major and minor issues need to be addressed. 