Abstract Marsh gas samples collected from fresh-water marshes in Minnesota, Louisiana and Delaware, having waters near neutrality and weakly negative to weakly positive Eh, yielded larger methane flows than brackish water and salt-water marshes in Delaware and Louisiana with more negative Eh values. Carbon dioxide, nitrogen, carbon monoxide, hydrogen, and propane are other common constituees of the marsh gases. Hydrogen sulfide is less abundant in the fresh-water than in the brackish and salt-water marshes. Other marsh conditions relating,to methane genesis include salinity, sulfate content, turbidity, rainfall, tidal action, and source material.

Abstract The Ostracoda of the upper 1 cm of sediment of the Gulf of California have been studied in a preliminary way. About 100 species have been recognized, only 40 of which have been tentatively identified with described species. The majority of the ostracode specimens were obtained in the shallower parts of the Gulf at depths of 100 fathoms or less.