AFRICAN TURTLE. 363 



rebellious set, and will often chase the old birds 

 round the cage ? and again and again present them- 

 selves before their face, as often as they turn 

 away from their solicitations; at the same time 

 they keep up a continual flapping with their 

 wings, utter a plaintive, whining note, and peck 

 at the sides of their parents' bills, trying every 

 stratagem to make them yield to their entreaties. 

 The old birds, however, as if conscious that there 

 was no supply, or that it was no longer needed, 

 obstinately refuse to pay any regard to the 

 demands made upon them : or they are not pre- 

 vailed upon until after a long time, and till wearied, 

 as it were, with the perpetual teazings of their 

 offspring. The difficulty experienced by the young 

 in effecting their object is greater as they advance 

 to the age at which they are able to take care 

 of themselves. Probably the secretion in the 

 parent's crop is dependent upon a certain degree 

 of excitement caused by maternal affection ; and, 

 after a time, when this excitement wears off by 

 reason of the increasing age of the young bird, it 

 is with difficulty elaborated. At length it ceases 

 altogether ; yet the habit of the young coming to 

 its parent to be fed is kept up for a while. This 



