In Vanna Lava (Port Patterson) a man will not even walk behind his mother-in-law along the beach until the rising tide has washed away the trace of her footsteps. But they may talk to each other at a certain distance. It is quite out of the question that he should ever pronounce the name of his mother-in-law, or she his[25]. On the Solomon Islands, beginning with his marriage, a man must neither see nor speak with his mother-in-law. If he meets her he acts as if he did not know her and runs away as fast as he can in order to hide himself[26]. Among the Zulu Kaffirs custom demands that a man should be ashamed of his mother-in-law and that he should do everything to avoid her company. He does not enter a hut in which she is, and when they meet he or she goes aside, she perhaps hiding behind a bush while he holds his shield before his face. If they cannot avoid each other and the woman has nothing with which to cover herself, she at least binds a bunch of grass around her head in order to satisfy the ceremonial requirements. Communication between them must either be made through a third person or else they may shout at each other at a considerable distance if they have some barrier between them as, for instance, the enclosure of a kraal. Neither may utter the other’s name[27]. Among the Basogas, a negro tribe living in the region of the Nile sources, a man may talk to his mother-in-law only if she is in another room of the house and is not visible to him. Moreover, this race abominates incest to such an extent as not to let it go unpunished even among domestic animals[28]. Whereas all observers have interpreted the purpose and meaning of the avoidances between near relatives as protective measures against incest, different interpretations have been given for those prohibitions which concern the relationship with the mother-in-law. It was quite incomprehensible why all these races should manifest such great fear of temptation on the part of the man for an elderly woman, old enough to be his mother[29]. The same objection was also raised against the conception of Fison who called attention to the fact that certain marriage class systems show a gap in that they make marriage between a man and his mother-in-law theoretically not impossible and that a special guarantee was therefore necessary to guard against this possibility. Sir J. Lubbock, in his book _The Origin of Civilization_, traces back the behaviour of the mother-in-law toward the son-in-law to the former ‘marriage by capture’. “As long as the capture of women actually took place, the indignation of the parents was probably serious enough. When nothing but symbols of this form of marriage survived, the indignation of the parents was also symbolized and this custom continued after its origin had been forgotten.” Crawley has found it easy to show how little this tentative explanation agrees with the details of actual observation.