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The temperature range of growth of certain marine bacteria varied considerably, being from as small as 15° to as great as 50 °C. The lowest temperature of growth was −7.5° and the highest was 45°. All the organisms grew at 0° except four. The optimum was generally from 20° to 25°, but there were many exceptions, some growing best at 37°, and one growing equally well from 20° to 42.5°.

A metal water bottle acting on the principle of a piston in a water tight cylinder has been devised as a simple, strong, and easily operated apparatus for taking water samples for bacteriological purposes at any depth without the danger of contamination by the upper layers of the sea.

When the skin of halibut is seeded with certain marine chromogenic bacteria, that produce pink, orange and yellow pigments in pure culture and that ordinarily occur on the skin of dead halibut, it becomes pink or yellow, as well as sour, in ten days at 0 °C.

It was found that a 1% solution by volume killed 2000 million bacteria in a distilled water suspension at 25° in 10 minutes, but when the suspension was made with tap water containing 3 mg. of total solids the time was increased to 15 minutes, and only 425 millions were killed in 20 minutes when the suspension was made with bilge water containing 0.86% organic matter.When the temperature was lowered the lethal effect was reduced so that a 2.5% solution which killed 2000 millions in 15 minutes at 25° only killed 125 millions at 4°.Ice was sterilized under commercial conditions with 5 parts of formaldehyde to 100,000 parts of water.

Experimental results indicated that metals used in a bacteriological water sampling bottle were not toxic to a certain marine organism within an incubation period of 60 minutes. After this elapse of time the bactericidal effect became apparent.