Morton-- English and Scottish: habitational name from any of the many places called Mor(e)ton, named in Old English as ‘settlement (tun) by or on a marsh or moor (mor)’. Swedish: variant of Martin. French: contracted form of Moreton 2. Americanized form of one or more like-sounding Jewish surnames or of various other non-English names bearing some kind of similarity to it.
Marmaduke-- I found the meaning for this at behindthename.com (not the surname section.) Derived from the Old Irish name Mael Maedoc meaning "disciple of Saint Maedoc". Maedoc was the name of several early Irish saints. Also, according to my geneology sources, most of those with the surname, came to the U.S. from Ireland.
Melendy-- Of Scottish, Welsh, or English origin, but uncertain etymology. It is recorded in the 17th century in Scotland and subsequently in Boldre, Hampshire. Most probably it is a habitational name from Welsh melin ‘mill’ + dy, lenited form of ty ‘house’. Place names of Welsh origin are found not only in Wales and western England, but also in southern Scotland, where Welsh was spoken in earlier centuries.
Wells-- English: habitational name from any of several places named with the plural of Old English well(a) ‘spring’, ‘stream’, or a topopgraphical name from this word (in its plural form), for example Wells in Somerset or Wells-next-the-Sea in Norfolk. Translation of French Dupuis or any of its variants.
Mackling-- I couldn't find this particular name but possibly it's a variant of the surname, Macklin. Macklin is English in usage but unexplained in etymology. It occurs chiefly in Hampshire and Wiltshire. It is also established in Ireland, where it may be an Anglicized form of Gaelic Mac Giolla Eóin (see McLean).