The main site of the museum remained the Barrault House, but in 1885, the town of Angers decided to purchase the Soye collection, which consisted of several thousand fossil samples. At this point, the number of palaeontological specimens becomes too large for the premises and are placed in the Old Town Hall, constituting a Palaeontological Museum. The geological collections joined them soon after. In the same year, a Holzmaden ichthyosaur cast is added to the collections, purchased at the Cantonal Museum of Geology in Lausanne, where the original still stands. An original ichthyosaur fossil from Holzmaden would be added to the collections later.