^°i^^] COLE, J'aHafioiis in the Block-backed Magpie. 53 



After the first moult, tlie adult pluuiage is indicated, the third 

 moult bringing the plumage to perfection. The specimens 

 figured are fully plumaged matured male birds, all having reared 

 young. In some instances, I observed two clutches, and others 

 one from each pair, under observation. Fig. A was mated to a 

 typically marked female. In the spring, and early summer of 

 1916, this pair of birds reared four young ones, two being typi- 

 cally marked, whilst two were marked as in Figs. B and C. Fig. B 

 was mated to a typically marked female. In the spring of 19 19, 

 this pair reared two young ones, one Ijeing typicall}' marked, the 

 other as Fig. D. 



Fig. C was mated to a female marked as Fig. D. Three young 

 were observed, one typical, one as Fig. C, and one as Fig. E. 



Fig. D was mated to a female marked as in Fig. C. Two 

 young were reared, one resembling Fig. B, the other Fig. C. 



Fig. E was mated to a female as in Fig. B. They reared 

 four young, one typically marked, one resembling Fig. B, one 

 Fig. C, and one Fig. D. 



From these observations, fifteen young birds were reared, five 

 being typically marked = 33 1-3 per cent.; ten being variations 

 = 66 2-^ per cent.. One hundred per cent, of the progeny of 

 other pairs typically marked, and mated, under observation, were 

 true to type. 



From the observations, it will be found that many pairs breed 

 true to type, whilst others perpetuate variations. 



Complete to partial albinoism at times occurs in this species. 

 It is significant that black may turn white, whilst white does not 

 turn black. If this were so, variations upon the back markings 

 of the species G. leuconota may be as common as in G. tibicen. 



Fig. F depicts a male specimen of G. leuconota from southern 

 A'ictoria. 



I had under observation in captivity a variation of G. tibicen 

 that was becoming an albino. The laack and the tail were the 

 first parts to become pure white, wdiilst the remainder of the 

 black feathers upon the body became streaked or mottled with 

 whitish. The irides from a deep red hazel became paler 

 (pink in an albino). This bird before its third moult was 

 accidentally killed. The specimen referred to as a partial albino 

 was also the progeny of a partial albino male, tibicen, which 

 was mated to a typical female, tibicen, and was a conspicuous 

 bird for several years to travellers and others between Wan- 

 garatta and Springhurst. This pair of birds for several years 

 built adjacent to the railway line, their progeny varying from 

 typical colourings to variations, as already depicted in this ar- 



