Henry Holiday interpreted “his hair” in
001 “Just the place for a Snark!” the Bellman cried,
002 As he landed his crew with care;
003 Supporting each man on the top of the tide
004 By a finger entwined in his hair.
as the Banker’s hair, not as the Bellman’s hair. That also seems to be the the common understanding of the ambiguously used pronoun “his” since The Hunting of the Snark was published in 1876.