Newell, Edna Catherine2016-06-152016-06-1519491949b14749154(OCoLC)07889969(OCoLC)ocm07889969https://hdl.handle.net/2144/16500Thesis (M.A.)--Boston University, 1949. This item was digitized by the Internet Archive.en-USBased on investigation of the BU Libraries' staff, this work is free of known copyright restrictionsThe construction and evaluation of a test of visual discriminationThesis/Dissertation