The amount and

Predation on juvenile pink salmon (Oncorhynchus gorbuscha) and chum salmon (O. keta) by yearling coho (O. kisutch) was studied in marine enclosures in Masset Inlet, B.C. These experiments demonstrate that coho prey selectively upon pink salmon even when chums are both significantly smaller and more abundant than pink salmon. Reexamination of the results of similar experiments conducted in Burke Channel, B.C., also confirms that mortality was biased towards pink salmon. Prey species may be more important than prey size for coho that prey upon mixed populations of pink and chum salmon during early sea-life.

to 7000 mg/ 100 ml in human plasma (3). The flow of aqueous humor is across the lumen, from inner to outer wall. The inner wall has openings that are 0.1 to 1.0 Am in diameter, the outer wall has large openings up to 80 ,um which lead to the veins in the episclera. With these facts in mind, perhaps what has been seen in both dog artery and human canal of Schlemm is a structure common to many endothelial cells. These projections may take part in the exchange of fluid across the endothelial cell by increasing surface area, rather than having an effect on the longitudinal flow of fluid. Their frequency was much greater in the dog pulmonary artery than in the Schlemm's canal in the human, which might relate to a more rapid rate of flow of fluid across the endothelial wall in the lung than in the eye.

Predation may be a major source of size-dependent mortality of Pacific salmon (Oncorhynchus spp.) during early sea life. Our experiments conducted in large saltwater enclosures demonstrated that coho (Oncorhynchus kisutch) are size selective when preying on juvenile chum (O. keta) salmon. Yearling coho (112–130 mm fork length) consumed significantly more smaller chum over a range in prey size of 43–63 mm fork length. We hypothesize that the intensity of size selectivity by coho and other predators is variable, depending on the relative sizes of the predators and prey.

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