Open page 36, last paragraph. He says that, Nayars are the only matrilineal caste in Kerala. Its absolutely bullish. Thiyyar followed matrilineal system.see:http://books.google.com/books?id=7Hue54bWk6IC&pg;=PA18&lpg;=PA18&dq;=Thiyya+matrilineal&source;=bl&ots;=XJifXKZdQI&sig;=m86sC9W9gKfjDbWigawum7KkIhk&hl;=en&sa;=X&ei;=rVlPUfHlOo3ligK2tYC4Bg&ved;=0CD4Q6AEwAg#v=onepage&q;=Thiyya%20matrilineal&f;=false