34 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. 143 



coracoideus in the table. None are especially good fliers. Podiceps 

 has large legs which it uses in swimming. Aramides has the largest 

 legs of all, which it can use in stalking through the swamps. Cro- 

 tophaga spends much time on foot. Among the other birds in this 

 table, the trogons, swallows, and kingfishers use their legs very little. 



Let us examine the master table (table i) with both the muscle size 

 and flight areas in mind to see whether these values are related to the 

 habits and activities of the bird. There appears to be a correlation ; 

 some illustrations may serve as examples. In the stork, Mycteria, 

 the large legs indicate much ground work, yet the pectorals suggest 

 medium flying power, the heart suggests ability to sustain activity, 

 while the moderate wing area together with a high aspect ratio mean 

 efficient flying and gliding once the bird is airborne. In the duck, 

 Aythya, a medium-sized leg indicates moderate use, the pectoralis is 

 fairly powerful, but the wings are small, thereby requiring a faster 

 beat. An interesting comparison may be made in the two vultures. 

 Cathartes has a much larger wing area and a greater aspect ratio than 

 Coragyps, indicating more soaring and gliding, while the heart of 

 Cathartes is small so that less sustained effort is possible. This agrees 

 with the performance. Coragyps soars much less and flaps frequently 

 in flight. 



In the hawks large legs are useful in capturing prey, while large 

 wings and high aspect ratio go with easy flight and soaring, but a 

 medium-sized heart prevents long sustained effort. 



All the rails have large legs but vary much in wing area. Their 

 hearts can support moderate activity. The jacana could be more active 

 than the rails, having a larger heart, larger pectoralis, and very large 

 wings, but medium-sized legs. Therefore, it could be in the air longer 

 and fly with slower strokes. Likewise, the shore birds, with moderately 

 large hearts and pectoralis and large wings with high aspect ratio, 

 would be good fliers. 



The large wings, high aspect ratio, but rather moderate pectoralis 

 and fair-sized heart of larids suggest soarers. In the columbids, large 

 pectoralis, large wings, but moderate aspect ratio and fair-sized hearts, 

 with good tails, indicate good flying. Parrots as well as some columbids 

 have fair-sized legs and good flight mechanisms. Cuckoos could not 

 use their wings as much as some birds do, since they possess small 

 pectoral muscles and small hearts. With their large wings, the beat 

 need not be fast. The large wings of owls, moderate hearts and 

 pectoral muscles, together with large legs, enable them to pounce 

 noiselessly and seize prey. The large wings and fairly large pectoral 



