ABSTRACT
Thereaderwhohasgonestraightthroughthebookmaybeconvincedat thispointthatnoneofthethreedimensionsofvisualperception-time, space,andcolor-canprofitablybestudiedalone.Ifthereisanexception thatprovesthisrule,itwouldbeDr.Piantanida'schapter,whichdeals withgeneticcontrolofthespectralabsorbancesoftheretinalphotopigments.Eventhesespectralpropertiesundoubtedlyevolvedinrelationto howthepigmentsareusedandwhatisdonewiththesignalstheygenerate. Forthemoment,however,itisconvenienttoignorethoselargerissues, becauserecentresultsinthemolecularbiologyofrodandconepigments aresoexciting.
