### Instruction: Which of the following does not fit with the others on the list? Please explain your reasoning.
Galaxy M81
Black Eye Galaxy
Pinwheel Galaxy
Andromeda Galaxy
Sombrero Galaxy
### Response: Of the 5 galaxies on the list, the Sombrero Galaxy is the only one that is not clearly a spiral galaxy. While some sources do describe the Sombrero Galaxy as a spiral galaxy, most acknowledge that it has an usual shape that differs from most spiral galaxies.