Order I
Pygopodes. -GREBES, LOONS, and Auks.
Ducklike birds with generally sharply pointed bills; feet webbed, placed far back near the tail; tarsus much flattened; hind toe, when present, with a lobe or flap; bill without toothlike projections; tail very short and sometimes apparently wanting.
A. Toes four, tipped with a broad nail. a. Toes with lobate webs. Family Podicipida:
GREBES (Fig. 5, a), p. 56. ... b. Toes webbed. Family Urinatoridæ: LOONS (Fig. 5, 6), p. 58. ... ...
B. Toes three, tipped with a sharp nail. Family Alcida: AUKS, MURRES, and PUFFINS (Fig. 5, c), p. 60. 3 a b