Note:   Several languages (Italian, Greek, Spanish, French, etc.) are derived from old Latin and contain the words "di, de, da  ..........   li, le, lo" .
" di, de, da " =   from, of                 " li, le, la, lo " =   the
You will often find these words used in names.   At one time they were probably used to describe a person's parent, their personal traits or a place of origin.   Di Luca = son of Luke;
Di Appolonia = son of Appolonia, Di Abruzzi = from Abruzzi.  La Rocca = the rock.   The endings (masculine form= "o", feminine form= "a", no particular gender, plural= "i" ) have been interchanged throughout time depending on the scribe/clerk recording it.  Eventually, the words and the names may combine - the same way words become shortened (contracted) in the English language.   DiAppolonia, di Appolonia, D'Appolonia, Di Appolonia, Lo Appolonio, L'Appolonio are all forms of the same root name; Appolonia (Apolloni).  A different example is Della Rocca = of/from the rock.  Sometimes the prefix or suffix of a name is "lost" or "dropped" D'Apolonia may become Apolonia, D'Apoloni or D'Apolon .  Occasionally names are combined into single words and capitalization is no longer used within the name (Diappolonia, Dappolonia, Dellarocca, etc.).