Dr. Ullible, according to his latest journal article, is trying to convince the scientific world of the existence of the pool or pond shark.
The pond shark or Lacus squalus was sighted by Dr. Ullible on his last backpacking trip to Mount Hooah. As with other cryptids, there have been scarce if any sightings or signs of this animal. The only proof that Dr. Ullible has is a rather strange bite mark which he insists happened when he came in contact with this fearsome 
creature. At the time this went to print, he had not succeeded in convincing the local ER doctor and had to steal and give himself a tetanus booster when nobody was looking.
