Refactor the unstructured text into a valid JSON dictionary. The key names follow the Darwin Core Archive Standard. If a key lacks content, then insert an empty string. Fill in the following JSON structure as required: {"catalogNumber": "", "order": "", "family": "", "scientificName": "", "scientificNameAuthorship": "", "genus": "", "subgenus": "", "specificEpithet": "", "verbatimTaxonRank": "", "infraspecificEpithet": "", "identifiedBy": "", "recordedBy": "", "recordNumber": "", "verbatimEventDate": "", "habitat": "", "occurrenceRemarks": "", "associatedTaxa": "", "country": "", "stateProvince": "", "county": "", "municipality": "", "locality": "", "decimalLatitude": "", "decimalLongitude": "", "verbatimCoordinates": "", "minimumElevationInMeters": "", "maximumElevationInMeters": ""}
 u s.n.  MV* E 1878-04-28  Viola rotundifolia 4Y  fred h. horsford 5T   ir GRPM 42753  MALPIGHIALES si  united states vx  chittenden fn+sR     b viola     +YH  ROTUNDIFOLIA   9 O!P 1507517  q : michx.  +J 2; charlotte  ua.xg VIOLACEAE     m?. Vermont 
{"catalogNumber": "1507517", "order": "Malpighiales", "family": "Violaceae", "scientificName": "Viola rotundifolia", "scientificNameAuthorship": "Michx.", "genus": "Viola", "subgenus": "", "specificEpithet": "rotundifolia", "verbatimTaxonRank": "", "infraspecificEpithet": "", "identifiedBy": "", "recordedBy": "Fred H. Horsford", "recordNumber": "s.n.", "verbatimEventDate": "1878-04-28", "habitat": "", "occurrenceRemarks": "GRPM 42753", "associatedTaxa": "", "country": "United States", "stateProvince": "Vermont", "county": "Chittenden", "municipality": "", "locality": "Charlotte", "decimalLatitude": "", "decimalLongitude": "", "verbatimCoordinates": "", "minimumElevationInMeters": "", "maximumElevationInMeters": ""}