A picture of a crocodile mummy being scanned.

A picture of a crocodile mummy CT scan showing possible rocks inside its belly.

A picture of baby crocodile mummies stuck to the back of an adult crocodile mummy.

the wrapped crocodile mummy in the Stanford lab.

the unwrapped crocodile mummy's CT scans.

the unwrapped crocodile mummy's CT scan.

Mask of the Mummy There's a real crocodile behind that mask, according to new computed tomography (CT) scans of a 2,000-year-old Egyptian mummy (pictured). The 8-foot-long (2.4-meter-long) artifact—wrapped in once colorful linen and outfitted with a stylized mask—is one of two crocodile mummy bundles scanned this month at the Stanford School of Medicine in California.Scans of the bundle above show a "mishmash of bony parts" from at least two Nile crocodiles, including two skulls, a shoulder bone, and possibly a femur, according to conservator Allison Lewis, a fellow at the Phoebe A. Hearst Museum of Anthropology in Berkeley, California, where the mummies are kept.Their origins unknown, the mummy bundles were purchased by philanthropist Phoebe Hearst in Egypt at the turn of the 20th century. The artifacts were recently restored and studied before going on display this week in the museum's new exhibition, "Conservator's Art: Preserving Egypt's Past."Mummifying animals was a common practice among ancient Egyptians, who embalmed thousands of crocodiles and buried them in mass graves as offerings to the crocodile god Sobek, according to the museum. (See "Mummy Birds Recovered From Egypt Factory.")—Christine Dell'Amore

Photograph courtesy John Stafford, Stanford School of Medicine