social practices. One who applies a given term of relationship to another person has to behave towards that person in certain definite ways. He has to perform certain duties towards him, and enjoys certain privileges, and is subject to certain restrictions in his conduct in relation to him. These duties, privileges and restrictions vary greatly in number among different peoples, but wherever they exist, I know of no exception to their importance and to the regard in which they are held by all members of the community. You doubtless know of many examples of such functions associated with relationship, and I need give only one example.
In the Banks Islands the term used between two brothers-in-law is wulus, walus, or walui, and a man who applies one of these terms to another may not utter his name, nor may the two behave familiarly towards one another in any way. In one island, Merlav, these relatives have all their possessions in common, and it is the duty of one to help the other in any difficulty, to warn him in danger, and, if need be, to die with him. If one dies, the other has to help to support his widow and has to abstain from certain foods. Further, there are a number of curious regulations in which the sanctity of the head plays a great part. A man must take nothing from above the head of his brother-in-law, nor may he even eat a bird which has flown over his head. A person has only to say of an object "That is the head of your brother-in-law," and
