Helen, I just posted on the roots web MARSELIS Board that the DNA results for my son who goes back to the immigrant Pieter Marcelis has a match with a Herbert Alton MARSELAS!! The genetic distance is 3 but from generation 8 (66%)back it gets into the 90%s.
So far on a fast search this morning this MARSELAS family was found to be in Maryland on the 1930 and 1940 Censuses and the name was spelled as MARCELLUS then. Spelling varied. Do you think this could be the same line you have been looking for?
This is very exciting IF SO because it is our first clue to a definite connecting link to the Dutch family Marcelis with all its 20+ variant spellings.