The Pride of Sheboygan was a spaceship based out of Vega. It was a survey vessel for the Iapara Investiture. Its mission was to capture alien life forms to be brought back to Vega for dissection.
On one mission the Pride of Sheboygan suffered an accident, releasing all aliens it had stored in containment. One alien was a Memeovore, which wiped a year's worth of memories from the surviving crew. The Fifth Doctor and Vislor Turlough later arrived on the ship to take the Memeovore to Soloto. (PROSE: Piecemeal)