Sooty and Slender-billed Shearwater (Puffinus griseus and P. tenuirostris) Because these two species are easily confused all sightings were called Sooty/Slenderbills. However, of the few birds that were seen well, none were Slenderbills. Most of the sightings (excepting those off the Baja Peninsula) were of birds gravitating towards the southeast. Juan Fernandez Petrel (Pterodroma externa) 6 collected All of the birds which were seen well were identified as the sub- species externa and the writer is convinced that there were no cervicalis in the area. The distribution was somewhat confusing, but increasing abundance from east to west was evident, especially in the countercurrent area where the highest densities for the cruise were recorded. Although Wedge-tailed Shearwaters were present and most abundant in the same area, a day to day comparison of ratios demonstrates that there was little cor- relation of numbers between the two species. That the two have different ecological requirements may also be inferred from a comparison of the eastern distribution within the survey area. Whereas Wedge-tails were found along the easternmost portions of the track, no P. externa were seen east of 105° west longitude. Further suggestion of ecological re- quirements may be inferred from the north-south distribution of the two species. Virtually no Wedge-tails were seen south of the southern border of the North Equatorial Countercurrent, whereas Juan Fernandez Petrels were seen as far south as the cruise track went. Six specimens of Juan Fernandez Petrels were collected along the westernmost portion of the cruise. All were of nonbreeding age, had heavy body molt, and were in a light fat condition. Cook's Petrel (Pterodroma cookii) A few birds of this species were seen about three hundred miles west of Baja in mid-October. Although only a few were seen, there was some suggestion that they were in southeasterly migration. Black-winged Petrel (Pterodroma hypoleuca nigripennis) A total of 34 birds was identified as this subspecies between five and fifteen degrees north latitude on the western leg of the cruise. There was no suggestion that they were migrating. It is interesting and perhaps significant that the range met but did not overlap the range of the White-winged Petrel (P. leucoptera) recorded on the survey. It is also significant (?) that no hypoleucans of the subspecies hypoleuca were recorded on this cruise; they were said to have been present in approximately the same area in August-September.