Breed of domestic cat (7)
(Other definitions for siamese that I've seen before include "Cat - Thai?" , "like a cat" , "Thease twins are joined at birth" , "Twin" , "sort of twins" .)
(Other definitions for tortoiseshell that I've seen before include "Domestic cat - or little shoes (anag)" , "Mottled plated ornamental substance" , "Butterfly - cat" , "Ornamental material" , "Butterfly - yellow-brown mottled material" .)