"True horns" have a bone core that is covered in a permanent sheath of keratin, and are found only in the bovids. "Antlers" are bony structures that are shed and replaced each year; they are found in deer (members of the family Cervidae). They grow from a permanent outgrowth of the frontal bone called the pedicle and can be branched, as in the white-tailed deer ("Odocoileus virginianus"), or palmate, as in the moose ("Alces alces"). "Ossicones" are permanent bone structures that fuse to the frontal or parietal bones during an animal's life and are found only in the Giraffidae. "Pronghorns", while similar to horns in that they have keratinous sheaths covering permanent bone cores, are deciduous.