separate since they basically agree on all characters mentioned above. However, they differ in length of the legs with the legs of a Wilson's generally extending beyond the tail when it flies. At other times it will dabble its long legs in the water. Flight may also be a useful character but I did not see enough Oceanites to be sure how to tell them from Oceanodroma. However, I did see a flight difference between Leach's and Galapagos' Storm Petrels. Leach's flies like a small nighthawk with deep wing beats while tethys has a stiff wing beat due to the smaller wings of this species. I can find no plumage or size characteristic to separate Black Storm Petrels from Markham's Storm Petrels in the field. The area of occurrence (Markham's in the colder water along the equator) and the ship following tendency of the Black Storm Petrel were used to identify these species in the field. They are both smaller than the Sooty Storm Petrel of the central Pacific and larger than dark-rumped Leach's from which they also differ in having a more deeply forked tail. FIGURES 11-13 show the distribution of these Storm Petrels. It is likely that many of the unidentified Oceanodroma on the western two legs along the equator were Harcourt's which I overlooked at the time. White-faced Storm Petrel (Pelagodroma marina) This species was fairly common near the equator on the outer two legs but not found near the Galapagos. Competition with the resident storm petrels probably excludes it from this area. In the region where they occurred, sea surface temperatures were less than 20°C which is possibly a limiting factor in the species. In early summer they were not found here when the temperatures were well above 20°C. Blue-faced Booby (Sula dactylatra) Red-footed Booby (Sula sula) Adults of both these species were members of eastern Pacific populations