The prohibition of marriage within the _gotra_ or exogamous section
bars the union of persons related solely through males. In addition
to this, according to Hindu law a Brahman must not marry a girl of his
mother's or maternal grandfather's _gotra_, or one who is a _sapinda_
of his father or maternal grandfather. Mr. Joshi states that _sapindas_
are persons related through being particles of the same body. It is
also understood that two persons are said to be _sapindas_ when they
can offer _pindas_ or funeral cakes to the same ancestor. The rule
barring the marriage of _sapindas_ is that two persons cannot marry
if they are both as near as fourth in descent from a common ancestor,
and the relationship is derived through the father of either party. If
either is more remote than fourth in descent they apparently could
marry. If the relationship of the couple is through their mothers
in each case, then they cannot marry if they are third in descent
from the same ancestor, but may do so in the fourth or subsequent
generations. It is of no importance whether the intervening links
between the common ancestor and the proposed couple are male or female;
descent is considered to be male if through the father, and female
if through the mother. In practice, marriages are held to be valid
between persons fourth in descent from a common ancestor in the case
of male relationship, and third in the case of female relationship,
that is, persons having a common greatgrandparent in the male line
or a common grandparent in the female line can marry.
Other rules are that girls must not be exchanged in marriage between
two families, and a man may not marry two sisters, though he can
marry his deceased wife's sister. The bride should be both younger
in age and shorter in stature than the bridegroom. A younger sister
should not be married while her elder sister is single.