probably named after king John of England, 113;
his legal successor, his nameless dau., 115, 116, 117;
sole earl of O., 118;
his sister's son, Jon Langlifson, in 1263, 123;
succeeded in earldom of Orkney by Magnus II, 123;
his castle at Brawl, 133;
joint earl with David, 152 (n. 1);
Matilda not his daughter's name, 152 (n. 4).
Jon Langlifson, 74, 123, 124.