A juvenile Mastodon skull from Monmouth County, New Jersey

ABSTRACT. We report on the partial skull of a small juvenile Mammut americanum Kerr from the Monmouth brooks area of New Jersey. Most Pleistocene mammal specimens from the brooks occur as disarticulated fragments. This specimen, the left side of a skull, includes portions of the premaxillae, maxillae, nasals, lacrimals, frontals, and four teeth: three sequential deciduous premolars and the permanent tusk. The skull bones are loosely articulated and essentially unfused, and the reconstructed skull shows gaps representing unossified growth zones between bones. The two anterior left deciduous teeth (DP2 and DP3) are much worn and very fragile, while the posterior left deciduous tooth (DP4) is essentially unworn. The crypt for the left first molar (M1) is partially preserved. The interior of the braincase is characterized by shallow pitting; it is neither smooth nor does it show molding against gyri and sulci of the brain. The pits are not characteristic of the inner surface of a normal mammalian skull, and a...