Brief observations concerning the visual pigments of some selected fishes from Lake Heney, Quebec, a relict of glacial Lake Gatineau

The visual pigments and liver vitamins A of several races of Osmerus eperlanus mordax (rainbow smelt). Coregonus artedii (cisco), Myoxocephalus quadricornis thompsonii (deepwater sculpin). Cottus ricei (spoonhead sculpin) and Salrelinus namaycush (lake charr) have been examined. With the exception of Salvelinus and certain specimens of Osmerus , all were taken from Lake Heney. originally part of glacial Lake Gatineau at the time of the Champlain Sea episode, a marine inundation of the St Lawrence Lowlands that occurred some 9,000–12,000 yr ago. Osmerus has a rhodopsin with λ max at 512 nm and a porphyropsin at 541 nm, the latter practically absent in the sympatric dwarf (including young-of-the-year) and giant races of Lake Heney. Coregonus has a rhodopsin with λ max at 510–511 nm, perhaps with a trace of porphyropsin : Salvelinus has a rhodopsin and porphyropsin in variable amounts with respective maxima at 511 and 540 ± 2 nm . Of the two cottids. Cottus has a rhodopsin with λ max at 503 nm but Myoxocephalus is unusual in having a mixture of two rhodopsins with maxima separated by only 7 nm. located at 508 and 515 nm respectively. All species have the precursor of porphyropsin. 3-dehydroretinol. in their livers in proportions ranging from 17 to 50 per cent of the total liver retinols. These findings are related to observations on kindred species in other habitats or other regions, and the visual pigments of the two cottids are discussed in relation to the recent evolution of these fish.