a1. Smaller; length, 400 mm.; wing, 300. ridibundus (p. 95) a2. Larger; length, 600 mm.; wing, 450. vegæ (p. 97)
a1. Smaller; length, 400 mm.; wing, 300. ridibundus (p. 95)
a2. Larger; length, 600 mm.; wing, 450. vegæ (p. 97)
