NINTH ANNUAL REPORT. 



215 



OSTRICH LYING L\ llli. 

 From a photograph by C. W". [kcLc 



years to come — the only lingering representatives of the giant 

 birds which roamed the earth millions of years before the first 

 human being began the ruthless work of extermination. 



PART II. EXTERNAL STRL'CTLRAL .VDAPTATIONS TO CURSORI.VL 



HABITS. 



Functional radiation is developed to so remarkable a degree 

 in the Class of Birds, that we find representatives of many orders 

 which have become more or less specially adapted to a terrestrial, 

 cursorial life. Examples of these are the Tinamous, almost all 

 the members of the Order Gallinac, the Cranes, the secretary-bird 

 among the Hawks, the road-runner among the Cuckoos, and the 

 Larks among the Perching l>irds. Yet in all of these birds, ter- 

 restrial locomotion is indulged in only as an alternative of the 

 power of flight; and. except in the Tinaiuous, and to a less de- 

 gree among the Gallinac. life on the ground lias hail no a|)precia- 

 ble effect in lessening the wing pcnvcr. 



