W. Riemer 1950 Journal 19 Feb. Calif.: Contra Costa Co. Entire day spent in county at several localities looking for Triturus east of Lafayette. Walnut Creek examined at several points between town of Walnut Creek and State Hwy 24 near Concord. Stream flanked by orchards and open grass-land with scattered oaks. Terrain looks suitable for Triturus. Stream however shows signs of very severe flushing and few quiet suitable pools present even now with level relatively low. During flushings certainly no quiet water present. Best place to look probably near Walnut Creek [railroad] Tristle #2 about 0.5 mi. NNE Walnut Creek (town). Here stream 3-4 ft. deep and about 25 ft. wide No Triturus found; reasons obscure. Search also made in Contra Costa Canal where it crosses Yreg Ave SSE of Concord. Canal with sloping concrete sides, no noticeable flow and layer of algae on sides. Surrounding terrain in orchards, terrain flat. No Triturus. Another try 1-2 mi. SE Clayton in small tributary of Mt. Diablo Cr. Grassy hills with scattered oaks. Water clear, 11.4°C but probably highly seasonal. Seemingly an ideal spot but no Triturus.