The mother of a 13-year-old boy said she's outraged her son was banned from wearing a T-shirt in class that shows an anatomically correct U.S. Marine Corps bulldog.

Sandra Griffith, of Ellisville, Miss., said her son, Jordan, was was told by administrators at South Jones Elementary School to turn the shirt inside-out because the genitalia of the dog was deemed offensive.

"They said turn the shirt inside-out or go home and get a new one,'" Griffith told FoxNews.com. "I was in complete shock."  

The front of the USMC T-shirt shows the bulldog's face with the words: “If you are not the lead dog.” The back of the shirt shows the dog's rear with the message: "The view never changes."

Griffith said she was upset by the school's decision because the shirt was given to the boy by his older brother, Lance Cpl. Timothy Swann Jr., a member of 2nd Battalion, 9th Marines, who is serving in Afghanistan.

"He idolizes his brother," Griffith said. "The bond is very uncanny. If you want to talk about inappropriate and offensive, that was offensive to me."

School superintendent Tommy Parker was not immediately available when contacted Wednesday. In an interview with the the Marine Corps Times, he said the decision had nothing to do with the Marine Corps.  

"We're very pro-military," Parker told the newspaper. "We're one of the most conservative places in the United States."

Griffith said she met with Parker, who she claims told her the decision was "up to the principal."

"The last thing the superintendent said to me was that he, personally, didn't find it offensive and that no, it didn't go against the dress code. However, he said it was a very gray area," Griffith said.

The Marine Corps had no comment on the matter.

Fox News' Justin Fishel contributed to this report. 

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