Possibly Cocconeis costata W.Gregory 1855.
https://www.algaebase.org/search/species/detail/?species_id=37569

P. 242. Plate XXI.; fig 7. Shim, J. H. (1976). Distribution and Taxonomy of Planktonic Marine Diatoms in the Strait of Georgia, B.C. Phd. Thesis, UBC.

Plate XV, 79. Tynni, R. (1986). Observations of diatoms on the coast of the state of Washington. Geological Survey of Finland, Report of Investigation 75.