Keywords: CBBM25 233.png Larus bulleri <small>Hutton</small> Chroicocephalus bulleri <small> Hutton 1871 </small> ad Black-billed Gull adult wingtip pattern from below Catalogue of the birds in the British Museum http //www archive org/details/catalogueofbirds25brit Vol 25 Page 233 1896 Howard Saunders Osbert Salvin text PD-old CBBM25 Chroicocephalus bulleri illustrations Feathers of Chroicocephalus |