You may have a piece of Blenko glass. Blenko is a glass making company that opened in West Virginia in the late 1800s producing sheet glass and stained glass. In the 1930s they began to produce art glass.
Blenko's mid-century art glass includes whimsical bottles, vases, and paperweights in the shapes of animals and eggs. The fishbowl you mention may have been created for use as a vase. Most pieces were not signed but had a foil label which became a paper label during World War II.
Look for a book on mid-century glass such as "Mid Century Modern Glass in America" by Dean Six and Paul Eastwood, or Blenko catalogs reproduced by Schiffer books for collectors.
I've seen fish shaped Blenko vases for sale for between $50.00 and $100.00.