When is the husband liable for the loss of the mother-slave dower if it perishes while in his possession?

Primary text

If the mother-slave perishes while in the husband's possession, he is liable for her loss if the wife had demanded possession and he refused it, in which case he is treated like an usurper. If the wife had not demanded possession, he is not liable, because the mother-slave is merely an appurtenance to her mother.