The above two pages were copied from the History of Philadelphia, 1609-1884, Volume 3 by John Thomas Scharf, Thompson Westcott
They are extremely valuable in sorting out "who's who" in the Willcox family and especially identifying the following photo:
Thomas Willcox, founder of Ivy Mills in 1729, apparently had three sons:
John - left Pennsylvania and went to North Carolina. John's son, John, Jr. went on to Georgia and Telfair County.
James - stayed in Pennsylvania, didn't help with business management at Ivy Mills but instead managed his own paper mill in Ridley Creek until his death in 1769
Mark - managed the family business at Ivy Mills and upon his father's death inherited the mill which he left to his posterity:
"James M." in the photo above is Mark Willcox's son and Thomas Willcox's grandson. James M.'s sons Mark, James and Joseph are great-grandsons of Thomas Willcox. If I translated correctly....