ANSERINE. 145 



slender ; the head rather small, oblong, compressed, and 

 arched above. Bill stout, short or moderate, much higher 

 than broad at the base, gradually depressed toward the 

 end, of nearly equal breadth or narrowed, with large con- 

 vex unguis. Upper mandible internally concave, with a 

 medial tuberculate ridge, one or two series of tubercles 

 on each side, then a series of flattened lamellae, and along 

 the margin numerous lamellae, often enlarged at the end ; 

 tongue fleshy, thick, margined with pointed papillae or 

 fibres ; oesophagus long, narrow, a little enlarged below ; 

 stomach a transversely elliptical gizzard, of which the 

 lateral muscles are extremely thick, the tendons large, 

 the 'epithelium with two circular, somewhat concave, thick 

 grinding plates ; intestine long, rather narrow ; cceca long, 

 narrow at the base, then enlarged, and nearly cylindrical. 

 Trachea nearly uniform, with the inferior larynx simple 

 and compressed. Nostrils small or moderate, submedial, 

 oblong. Eyes small. Aperture of ear rather small. Legs 

 placed considerably forward, very strong, generally of 

 moderate length ; tibia bare for a short space ; tarsus 

 moderately compressed ; toes four, the first very small, 

 and free ; the anterior rather long, the outer little shorter 

 than the third ; the interdigital membrane full ; claws 

 short, arched, obtuse. Plumage rather full, close, and 

 firm, unless on the head and neck, where it is soft and 

 blended ; wings very long and broad ; primaries decurved, 

 the second and third longest, the first little shorter ; tail 

 short, rounded, of from sixteen to twenty-four feathers. 



The Anserinee inhabit chiefly the Arctic and Antarctic 

 regions in summer, migrating in autumn toward the 

 Equator. They are all gregarious, fly in lines when jour- 

 neying, have a strong and rapid flight, walk slowly, swim 

 with ease, but never dive in quest of their food, which 

 consists entirely of vegetable substances. Although they 

 feed chiefly on land, or in marshy places, they also, when 

 swimming in shallow water, pull up the submersed parts 



