as Schweinfurth (1961) has demonstrated very well in this journal. Perhaps the geographical facet of the natural history of these birds which has most signi ficance is that of their migrations (fig. 1). This is best documented in the case of the Bass Strait muttonbird or Short-tailed Shearwater, Puffinus tenuirostris (Ser venty, 1953 & 1956; Marshall & Serventy, 1956). Preceded by their parents, the fledglings in their hunger leave their rookeries in late April and early May. Shortly afterwards casualties are picked up along New Zealand beaches. By May the birds are found in numbers in Japanese seas; in July-Septem ber, they are over Bering Straits, Alaskan coastal waters and even reach into the Arctic Ocean. The