Jurassic strata of the foothills belt of Alberta and British Columbia have been designated as the Fernie formation after the locality in which they were first recognized. The formation overlies, with erosional unconformity, Triassic or Carboniferous strata and consists of a marine sequence of gray to black shales interbedded with minor amounts of thin sandstones. The upper beds grade through a transition zone into Lower Cretaceous strata which are non-marine and coal-bearing in the southern foothills but vary from non-marine to marine sandstones in the northern foothills. In the latter areas the sandstone sequence contains Jurassic and Lower Cretaceous fossils which suggests the absence of an apparent lithologic or time break between the Jurassic and Cretaceous systems. F ssil evidence from widely separated areas indicates a time range from Sinemurian to Argovian and indicates that the Jurassic seaways were fairly continuous at least in the deeper parts of the Rocky Mountain geosyncline. This would not necessarily rule out the existence of local uplifts in restricted localities of the area under discussion.