Palavra nova no meu caderninho de vocabulário: "chit" 

"In another words she is an insipid little chit. Is that what you mean?"  

A palavra "chit" tem o sentido de um voucher, ticket. 

Chit: an official note giving information or showing an amount of money that is owed or has been paid:

a chit for the dry cleaner's

Mas na frase do Henry James o sentido é de "a young and silly girl:"

just a chit of a girl

"Henry James  was born in New York City in the 19th century. As you might have noticed I love literature from this time. Actually he lived in England. He was American but I don't know if he became a citizen of England, if he became British...I have to check that information out"