Page:The birds of America, volume 7.djvu/252

184 sides of the thyroid bone in front, separating from the trachea, attaching themselves to the subcutaneous cellular tissue, and inserted into the furcula. Another pair arise from the same bone in front, spreading over the whole anterior surface of the trachea, then become collected on the sides, send off a slip to the costal process of the sternum, and continue narrow, to be inserted into the last arched half-ring of the trachea; thus forming what is called a single pair of inferior laryngeal muscles. Bronchi wide, each with 2S half rings.

FAMILY XLIII.— PROCELLARINvE. 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. (Esophagus very wide, often enormously dilated, espe- cially at its lower part, stomach small, moderately muscular; intestine of moderate length; cceca rather long; cloaca oblong or globular. Trachea simple, with a single pair of inferior laryngeal muscles.