“…He found differences in degree of reactions but these were so slight that a study like that made with mammalian bloods was not possible. Sasaki (1928) claims that he was able to distinguish the Japanese duck (Anas domestica erecta) from the Chinese goose (Anser cygnoides) with untreated sera and could distinguish the Japanese duck from the Muscovy duck (Cairina moschata) by specialized sera. These results would be more reliable were the possible error of the tests determined.…”