The sea bishop or bishop-fish was a type of sea monster

Sea monster

Sea monsters are sea-dwelling mythical or legendary creatures, often believed to be of immense size.Marine monsters can take many forms, including sea dragons, sea serpents, or multi-armed beasts. They can be slimy or scaly and are often pictured threatening ships or spouting jets of water...

 reported in the 16th century. According to legend, it was taken to the King of Poland, who wished to keep it. It was also shown to a group of Catholic bishop

Bishop

A bishop is an ordained or consecrated member of the Christian clergy who is generally entrusted with a position of authority and oversight. Within the Catholic Church, Eastern Orthodox, Oriental Orthodox Churches, in the Assyrian Church of the East, in the Independent Catholic Churches, and in the...

s, to whom the bishop-fish gestured, appealing to be released. They granted its wish, at which point it made the sign of the cross

Sign of the cross

The Sign of the Cross , or crossing oneself, is a ritual hand motion made by members of many branches of Christianity, often accompanied by spoken or mental recitation of a trinitarian formula....

 and disappeared into the sea.

Another was supposedly captured in the ocean near Germany

Germany

Germany , officially the Federal Republic of Germany , is a federal parliamentary republic in Europe. The country consists of 16 states while the capital and largest city is Berlin. Germany covers an area of 357,021 km2 and has a largely temperate seasonal climate...

 in 1531. It refused to eat and died after three days. It was described and pictured in the fourth volume of Conrad Gesner's famous Historiae animalium

Historiae animalium (Gesner)

Historiae animalium published at Zurich in 1551-58 and 1587, is an encyclopedic work of "an inventory of renaissance zoology" by Conrad Gesner, a doctor and professor at the Carolinum, the precursor of the University of Zurich...

.