Dogs of any coat type may be identified as either 'apple head' or 'deer head' Chihuahuas. Apple heads have rounded heads, close-set eyes, and relatively short ears and legs. Deer heads have flat-topped heads, more widely set eyes, larger ears, and longer, more slender legs. Deer heads were the breed standard conformation in the mid-20th century, but current breed standards defined by registries such as the AKC specify the apple-head conformation.