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It is becoming increasingly clear that this paper by Walker (1970)l is deservedly going to serve as an important reference for turbidite workers. I feel, therefore, that it is worth commenting, at this rather late stage, on the following paragraph (p. 233 ) : "A list of lateral changes related to the ABC index has been published by Lovell (1969a), but direct comparisons of proximal and distal characteristics are difficult because of the absence of stratigraphical control (my italics)". This statement is misleading, does not fit the known facts regarding the Tyee Formation, and does an injustice to the excellent stratigraphical work done over the years by many workers. I chose the Tyee Formation for a study of proximality in turbidites for the following reasons. (1 ) It is thick (5000+ ft (1525+ m) ), extensive (-4000 sq. miles (-10 240 k,m2) ), and largely undeformed and unmetamorphosed. (2) It has been the subject of several excellent previous and continuing studies (e.g. Baldwin 1964a, 1964b, Bird 1967, Dott 1966, Hoover 1963, and especially Snavely and Wagner 1962, and Snavely et al. 1964). ( 3 ) The Tyee Formation provides a rare example of a lateral transition from turbidites to nonturbidites (Baldwin 1965, Lovell 1969b, Snavely et al. 1964). This transition enables one to define the paleogeography of the dtpositional area without using lateral trends in the turbidites themselves, thus avoiding any circulac reasoning in the conclusions concerning the value of these IateraI trends as palaeogeographical indicators. The possibIe extent of the influence of vertical changes on these lateral trends can be assessed (Lovell 1969a, pp. 937-938, 1969b, p. 18). (4) The stratigraphical control over the formation as a whole is good (e.g. Baldwin 1961, 1964a, 1964b, Bird 1967, Dott 1966, Hoover 1963, McKeel and Lipps 1972, Snavely and Wagner 1964, Snavely et al. 1964, 1969, and others). I have no reason to change my (1968, p. 30) conclusion: "Both megafaunal and microfaunal evidence suggests that the Tyee Formation is most probably confined to Laiming's (1940) B-1 zone and Mallory's (1959) Ulatisian Stage, and to the middle Eocene Domengine Stage, of the standard West Coast Eocene (Weaver et al. 1944) ." This led me to the conclusion (Lovell 1968, p. 231) : ". . . one can say that the Tyee Formation was probably deposited in less than 4 million years, and quite possibly in under 2 million years." This issue of the stratigraphical control over the formation as a whole must not, of course