Catalogue no.1195, Mus. North. Well- preserved skull of "Castoroides ohioensis" but with the mandibles lost, both zygomatic arches missing, and the facial portions of the maxillae broken away; dental series complete and in good condition. "Castoroides" had cutting teeth up to 15 cm-long with prominently-ridged outer surfaces. These strong enamel ridges would have acted as girders to support such long teeth. Further, the deep masseteric fossa of the lower jaw suggests a very powerful bite. Perhaps their teeth could have acted as both wood-cutters and gouges. There is no clear evidence that the giant beaver felled trees or built dams, but a possible lodge was discovered near New Knoxville, Ohio around 1912. Part of a giant beaver skull and the lodge were located in a peaty layer surrounded by loam. In Ohio, there have been claims of a possible giant beaver lodge four feet high and eight feet in diameter, formed from small saplings. The recent discovery of clear evidence for lodge building in the related genus "Dipoides" indicates that the giant beaver probably also built lodges. Remains of the giant beaver, along with Paleo Indian artifacts and the remains of the flat-headed peccary, giant short-faced bear, and the stag moose were found in the Sheriden Cave in Wyandot County, Ohio. Fossils of "Castoroides" are concentrated around the midwestern United States in states near the Great Lakes, particularly Illinois and Indiana, but specimens are recorded from Alaska and Canada to Florida. In Canada, fossils of this species are commonly found in the Old Crow Basin, Yukon, and single specimens are known from Toronto, Ontario and Indian Island, New Brunswick. A hitherto overlooked 1891 record of a "Castoroides" skull from near Highgate, Ontario is the earliest for Canada. In Old Crow region, "Castoroides" fossils occur in deposits of the Sangamonian interglacial. The discovery of giant beaver remains in New Brunswick adds significantly to the Quaternary terrestrial mammal fauna of New Brunswick, and suggests that the terrestrial fauna was probably richer than earlier evidence indicated. The known North American distribution of giant beaver is not significantly changed by this occurrence. Specimens from the southeastern US have been placed in a separate species, "Castoroides dilophidus", based on differences in premolar and molar features.