Lastly, restrictions from marriage are occasionally found
applied to cases where the relationship is more or less imagi-
nary ; as in ancient Rome, where adoption had in some measure
the effect of consanguinity in barring marriage ; or among the
Moslems, where relation to a foster-family operates more fully
in the same way ; or in the Roman Church, where sponsorship
creates a restriction from marriage, even among the co-sponsors,
which it requires a dispensation to remove. Again, two members
of a Circassian brotherhood, though no relationship is to be
traced between them, may not marry, 1 and even among the
savage Tupinambas of Brazil, two men who adopted one
another as brothers were prohibited from marrying each
other's sisters and daughters. 3 But such practices as these
may reasonably be set down as mere consequences of the
transfer both of the rights and the obligations of consanguinity
to other kinds of connexion, and so do not touch the general
question.
To consider now the third group of customs, it is natural
enough that there should be found even among savage tribes
rules concerning respect, authority, precedence, and so forth,
between fathers- and mothers-in-law and their sons- and
daughters-in-law. But with these there are found, in the most
distant regions of the world, regulations which to a great ex-
tent coincide, but which lie so far out of the ordinary course of
social life as understood by the civilized world, that it is hard
even to guess what state of things can have brought them into
existence.
