This bird which is 19 inches in length, in the light phase has a plumage very similar to that of the larger Gulls. They nest by thousands on rocky islands of the north, often in company with Murres and Gulls. Owing to the filthy habits of the Fulmars, these breeding grounds always have a nauseating odor, which is also imparted to, and retained by the egg shell. Their single white eggs are laid on the bare rocks, in crevices of the cliffs, often hundreds of feet above the water. Size 2.90 × 2.00. Data.--St. Kilda, off Scotland. June 5, 1897. Single egg laid on rock on side of sea cliff. Collector, Angus Gillies. [Illustration 062: Fulmar.] [Illustration: egg.] [Illustration: left hand margin.] Page 63 86b. PACIFIC FULMAR. _Fulmarus glacialis glupischa._ This sub-species of the preceding, has a darker mantle than the common Fulmar; it is found on the northern Pacific coasts where it breeds on the high rocky cliffs, the same as its eastern relative. They nest in large colonies, every crevice in the rocks having its tenant. Their flight is graceful like that of the Gulls, which they closely resemble. They lay but a single white egg, the average dimensions of which are slightly smaller than those of the common Fulmar. Data.--Copper Is., Alaska. May 14, 1889. Egg laid in a crevice among the cliffs. 86.1. RODGER'S FULMAR. _Fulmarus rodgers._ Range.--North Pacific, breeding in large numbers on some of the islands in Bering Sea; south to California in winter. Very similar to the two preceding species except that the back is mixed with whitish, it is not believed to have a dark phase. Their breeding habits and eggs do not differ from the common Fulmar. The eggs are laid on the rocky cliffs during June. 87. SLENDER-BILLED FULMAR. _Priocella glacialoides._ Range.--Southern seas, appearing on the Pacific coast of the United States in the summer. This species has a paler mantle than the others of the family, and the primaries are black. The make-up and plumage of the whole bird is more like that of the Gulls than any of the others. They probably breed in the far south during our winter, although we have no definite data relative to their nesting habits. [Illustration 065: Pacific Fulmar. Slender-billed Fulmar.] [Illustration: deco.] [Illustration: right hand margin.] Page 64 88. CORY'S SHEARWATER. _Puffinus borealis._ This species probably breeds in the far south. It has been found only off the coast of Massachusetts and Long Island. This is the largest of our Shearwaters, and can be distinguished from the next species by its wholly white underparts, its light mantle and yellowish bill. We have no data relative to its nesting habits. 89. GREATER SHEARWATER. _Puffinus gravis._ Range.--The whole of the Atlantic Ocean.