If you are interested in natural history I would recommend a visit to the Booth Museum in Brighton. The museum is only small however a friend and I arranged to go 'behind the scenes' and were shown round the hundreds and hundreds of cabinets upstairs where everything is kept which isn't on show. There was every type of bird imaginable as well as hundreds of other animals. We were also shown round the taxidermy rooms where they were boiling a fox as we entered.