Last updated: 22 March 2013
I know nothing about this instrument beyond what the advertisement says - it came from a book of whimsical old adverts. The flutina was a bellows freereed instrument resembling the Cajun accordion; that is, it was bisonoric (a button would give different notes on pull or push) and the tonic of the major scale was on the pull, unlike most other modern melodeons or diatonic accordions. So this was presumably an analogue of the melodica that worked the same way; unlike the usual modern diatonic mouth organ, it would have had the major tonic on the suck. With two bass keys giving three or four bass chords, it would have the same musical capabilities as a one-row melodeon, but quieter.
Here are some pictures from an EBay auction of a slightly different model:
