OF SOUTHERN AUSTRALIA. 59 



the introduced egg with a lining of feathers, and so prevent 

 incubation ; but this is not generally resorted to, and the 

 strongest chick — the young Cuckoo — becomes the sole surviv- 

 ing member of the group. 



At another time the Cuckoo may be " unfortunate " in the 

 deposition of its egg within the cup-shaped cavity of the nest, 

 after which it will naturally remain unhatched. This is of 

 rare occurrence. 



One season I observed a double nest built in the whin, both 

 rooms perfect externally, but the lower one, with its entrance 

 facing the bush— an unusual position — finished internally. 

 The whole was new, and the upper one contained an egg of 

 the Narrow -billed Bronze Cuckoo, the lower a clutch of the 

 Tit, The birds appeared to be in excellent plumage, and 

 vrere probably old enough to remember the disappointment 

 of one or two past seasons, insomuch as related to the hard- 

 ship of rearing an uncongenial bird. To circumvent the 

 design of the Cuckoo, the second chamber was added to the 

 nest and the original abandoned. As with previous cases the 

 foreign egg remained unhatched, this giving the smaller bird 

 an opportunity to rear its own young. Rarely do small birds 

 add a second nest of this nature. 



Mr. G. J. Romanes has noted this inclination in the Common 

 Wren of Europe, and individual cases are elsewhere quoted. 



The " Yellow-tailed Tit " of the boys builds its nest not 

 only in hedges, but on the larger branches of various trees, 

 and, as has been previously noted, to the sticks of the lower 

 portion of a Crow's or Raven's nest, without any apparent 

 fear of their black neighbours. The parasitical mistletoe 

 (Loranthus) is also resorted to, as well as the wattle. 



An unusual case came under my notice, in which two 

 clutches of eggs had been placed in one nest, but requiring 

 the attentions of two females in their incubation, as proved 

 by the fact that both fluttered out of the nest on my approach. 



