OF SOUTHERN AUSTRALIA. 



tion in their nests because of the scarcity of insects in several 

 parts of the Wimmera. Just as spring seems to come 

 first to the plants near sea levels, and later to the " alpine" 

 forms, so does this species build a nest earlier in the valleys 

 than on the hills. This seems to be true even as regards the 

 small diiierence of 300 feet. 



The young birds remain with the old ones until they are 

 quite full-grown, and it is only when they are forcibly driven 

 away by the parents that they will face the world " on their 

 own." The keen observations of Mr. Geo. Graham, recorded 

 in his letters to me during August, 1898, state clearly the case 

 of forced individual migration : — "Three out of seven families 

 that occupy my paddocks have with them each a bird of last 

 season's breeding, and to all appearance it intends to stay 

 with them throughout the summer. When the next brood is 

 incubated the family will increase from three to five — two 

 always being the number of the brood here (Heytesbury) — 

 and, providing there are no accidents, it remains until about 

 next May, when one disappears, and shortly after another 

 goes. At this time there is a deal of chasing among the 

 Magpies, and T have concluded that it is the young male that 

 is being driven away. The young male becomes blacker and 

 darkens sooner than the female, as well as I can judge. I 

 think the parent male would not permit the opposite-sexed 

 young also to remain in camp during spring, so the junior 

 male has to go. Tf the young male should be allowed to 

 remain with the parents into the next season it does not mate 

 during its first year. T have also noticed the adult females of 

 two families trying to drive away the young females by 

 repeated attacks of sometimes thirty minutes' duration. The 

 old bird would pin the young one to the ground, but it seemed 

 to have no other effect than to make the young one afraid of 

 its mother. The male parent stands by, looking on, and takes 

 no active physical part in the contest. In both cases the 



