Cyclorhis, [536]

Cyclorhynchus, [316];

C. psittaculus, [318]

Cycnopsis cycnoïdes, [111], [132]

Cygninae, [111], [112], [135] f.;

young, [114]

Cygnus, fossil, [136];

C. bewicki, [112], [135], [136];

C. buccinator, [112], [135];

C. columbianus, [112], [135];