Before Jack Dorsey’s payment company was called Square, it was called Squirrel. This has been known for some time, but some new details were shared today by founder Jack Dorsey via Twitter.

According to Dorsey, payment service Square was almost called ‘Squirrel’ and the card reader dongle was made of wood and shaped like an acorn. The name Squirrel was known even before Square’s official announcement in December of 2009. As was the fact that the dongle was acorn shaped. But the images below are the first I’ve seen that show off the actual dongle design and logo in such detail.

Dorsey had lunch one day with Apple Senior Vice President of iOS Software Scott Forstall when he saw a POS system in the company cafe called ‘Squirrel systems’, so he decided to change the name of the company. Along with that meeting came a change in aesthetic…to a much more Apple-esque design.

Here’s the original branding and image of the ‘Acorn’ dongle that eventually became a square:

“What could have been: when Square was originally called Squirrel,” says Dorsey, “the reader was an acorn. Squirrel payments, anywhere.”

A shot of the company logo shared by Square creative director Robert S. Anderson:

He also shared the original Squirrel interface:

Another almost-name for the company? Seanote…get it, C-note?

And a 3D sketch shared by Anderson that was the inspiration for the Square logo:

The Square dongle being used on an old iPod:

And the moment that Dorsey renamed the company to Square:

Late last month, Square announced that it would be selling its card reader dongle at 1,000 AT&T stores, bringing its retail presence to 20,000 locations.