 British zoologist Francis Day , in his 1884 The Fishes of Great Britain and Ireland , noted that the common stingray was not eaten because of its " rank and disagreeable " flesh , and that Welsh fishermen used its liver oil as a treatment for burns and other injuries . In the present day , the pectoral fins or " wings " of this species are sold smoked or dried and salted , and it is also utilized as a source of fishmeal and liver oil . The liver is regarded as a delicacy in French cuisine , and used to prepare dishes such as <unk> de foie de <unk> and foie de <unk> en <unk> . 
