Kissing the Fat Man
When crossing the equator for the first time aboard a Navy ship you are known as a polywog. Once you cross you than become a shellback. One of the rites of passage is to kiss the fat man on the belly
as this unknown platoon member
is doing aboard the
USS Debuque Singapore bound

Watery Coffin
Here we have the shellback's putting an unknown platoon member into the coffin filled
with water and garbage
Aboard the USS Debuque

Garbage Fart Sack
Another thing that was required to become a shellback was to crawl through this fart sack filled full of garbage stored up for a week
just for this purpose.
Platoon members are unknown.

Lined up like cattle
As you can see a lot of crewmen
went through the
fart sack of garbage.
The one in green is LCpl Schmidt.
His where abouts today is unknown

Dunk Tank
The final step to becoming a shellback was to dive into the bottom of this tank filled with water and garbage. You had to retrieve the Golden Bolt of Neptune. You were than a shellback.