A number of rare animal skeletons dating back to 1880 have been stolen from a university in Sydney.

Last week a full Hippopotamus skull, a Hawksbill Sea Turtle skeleton with the shell, a Slow Loris skeleton and a full dog skeleton were taken from the museum that was established at Sydney University's city campus in 1890.

Police said the robbery is believed to have taken place between 11am last Wednesday and 9.30am the next morning.

Among those taken were a Slow Loris skeleton and a full dog skeleton. (NSW Police)

The skeletons are original specimens that were collected by a natural history dealer and taxidermist from Prague and date back to 1880, Acting Crime Manager from Inner West Police Area Command, Detective Acting Inspector Mark George said.

“We have released images of the stolen skeletons, which are rare and valuable. We hope the community can provide us with some fresh information that helps us recover the skeletons, and return them to the museum which is involved in the teaching of undergraduate students,” he said.

A Hawksbill Sea Turtle skeleton with the shell was also stolen last week. (NSW Police)