Family XLIII. PROCELLARINAE. FULMARS.
Bill generally shorter than the head, moderately stout, compressed; upper mandible with the ridge formed of two generally united plates, at the anterior part of which, usually about half the length of the bill, are the nostrils; the sides separated by a groove, the tip a decurved, compressed, pointed unguis; lower mandible with the angle very long and narrow, the tip more or less decurved. Head of moderate size, ovate; neck of moderate length; body compact. Feet of ordinary length, rather slender; tibia bare below for a short space; tarsus a little compressed, anteriorly scutellate; toes four, the first extremely small and elevated, with a conical deflected claw; anterior toes webbed; the third and fourth nearly equal. Claws arched, compressed, acute. Plumage full, soft, rather compact above. Wings long, rather broad, pointed, the first quill generally longest. Tail short, of from twelve to sixteen feathers. OEsophagus very wide, often enormously dilated, especially at its lower part, stomach small, moderately muscular; intestine of moderate length; coeca rather long; cloaca oblong or globular. Trachea simple, with a single pair of inferior laryngeal muscles.