Pg. 278-280, pl. 4. Hallowell member of Cobourg Formation. Lower Cobourg limestone of earlier reports. Lower part lithologically similar to underlying Sherman Falls formation. Upper part composed of gray medium- to coarse-textured massive limestone with very few intercalated shales; contrasts with more argillaceous Hillier member (new) above. Thickness about 100 feet. Present in southern Ontario, Canada, and northern New York. Age is Middle Ordovician (Mohawkian).
Type section: at Picton, Hallowell Twp., Prince Edward Co., Ontario, Canada.
Source: US geologic names lexicon (USGS Bull. 1200, p. 1650).
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