We also stumbled on the Zhejiang Museum of Natural History (浙江自然博物馆) in Anji (安吉), expecting some tiny dusty museum in the middle of nowhere — the way rural things often are. (Anji is a county-level city that belongs to Huzhou (湖州) which is a Tier 3 city.)
But no, this museum is massive, with a taxidermy collection covering all kinds of animals — even dinosaur fossils. The website says 200,000 specimens. And the entrance is totally free (although all free slots were booked, so we bought a 30 RMB movie ticket to get in).