1 88 THE MINDS AND MANNERS 



and almost comatose, show an instant reaction to the presence 

 of an owner it had not seen in weeks. Many birds form dislikes 

 for individual persons. This is especially noticeable in the 

 parrot tribe. A large male South American condor was friendly 

 enough with two of his keepers but would instantly attack any 

 other keeper or other person entering his enclosure, whether 

 wearing the uniform or not. With his two approved keepers 

 he was gentleness itself. 



Parasitic Nesting Habits. In the bird world there are a 

 few species whose members are determined to get something 

 for nothing, and to avoid all labor in the rearing of their off- 

 spring. This bad habit is known of the Old World cuckoos, the 

 American cow-birds, the South American rice grackle (Cassidix), 

 and suspected in the pin-tail whydah (Vidua serena). It 

 seems to reach its highest point in the cuckoos. It is believed 

 that individuals lay their eggs only in the nests of species whose 

 eggs resemble their own. Apparently much skill and intelli- 

 gence is required for introducing parasitic eggs at the most 

 favorable moment. This is equally true of other parasites. 



Curator Crandall has taken several eggs and young of the 

 rice birds from nests of two species of giant caciques in Cost* 

 Rica, but never saw an adult Cassidix. It is considered a very 

 rare species, but probably is more sly than scarce. Young 

 cuckoos eject unwelcome nestlings shortly after hatching. 



Daily contact with a large and varied collection of birds 

 great and small, gathered from every section of the habitable 

 regions of the"earth, naturally produces in time a long series of 

 interesting cases of intelligence and behavior. Out of our total 

 occurrences and observations I will offer two that reveal original 

 thought. 



Good Sense of the Wedge-Tailed Eagle. In discus- 

 sing bird intelligence with Mr. Herbert D. Atkin, keeper of our 

 Eagles Aviary and the cranes and water birds in the Flying 

 Cage, he called to my attention two species of birds which had 

 very much impressed him. Afterward he showed me all that 

 he described. 



