Manuscript notebooks, probably for 'Edda and Saga' (Home University Library 1931). The notebooks carry labels which seem to indicate references to box files as follows:
'No.1 Blue Box' (and on inside cover 'Refs in sagas to clothes, weapons etc.');
'Achille Serre Box No. 6' [notes on genealogies, Norwegian history etc];
'Achille Serre Box No. 12' [notes on poetry and drama];
'Achille Serre Box No. 20 [archaeological cuttings from Swedish papers].