Mastodon largest male specimens, the 35-year-old AMNH 9950 was tall and weighed , while another was tall and weighed . Like modern elephants, the females were smaller than the males. They had a low and long skull with long curved tusks, with those of the males being more massive and more strongly curved. Mastodons had cusp-shaped teeth, very different from mammoth and elephant teeth (which have a series of enamel plates), well-suited for chewing leaves and branches of trees and shrubs. Based on the characteristics of mastodon bone sites, it can be inferred that, as in modern proboscideans, the mastodon social
Mastodon (steam locomotive) the engine, where more than 20 copies were produced; these were identical except for having their cylinder bore increased to (from "Mastodon"'s ). The success of this engine inspired railroad president Leland Stanford to instruct Stevens to build an even larger locomotive, which would be the largest the world had ever seen up until that time. This engine, a 4-10-0 named "El Gobernador" (CPRR #237), looked virtually identical to "Mastodon", with the exception of being longer and having an additional pair of driving wheels. Unfortunately, this engine, unlike its predecessor, was doomed to failure. Sometime in the early 20th century,