In a housing (1), an internal space capable of housing an insect is formed, an opening (11) through which the internal space and an outside communicate with each other is formed, and a portion other than the opening (11) is closed so that the insect is incapable of passing through the portion. Rails (2) in a pair are disposed in parallel with each other on both sides of the opening (11) across the opening (11) on an outer surface of the housing (1), maintain a gap between a face, on which the opening (11) is formed, of the housing (1) and a cover (3) to have a size preventing the insect from passing through the gap, and slidably retain the cover (3) on the external side of the housing (1). A sample holder retains a sample, is slidably retained by the rails (2), and enables the sample to be exposed from the opening (11) to the internal space when being slidably retained by the rails (2) in the state of retaining the sample. The cover (3) and the sample holder retaining the sample can be slid between the rails (2) in the pair in a state in which one side of the cover (3) and one side of the sample holder come into contact with each other, whereby the cover (3) and the sample holder can be moved between a position at which the cover (3) covers the opening (11) and a position at which the sample covers the opening (11).
