PARASITIC WEAVERBIRDS 67 



combassou cliick was hatched but was drowned a few weeks later in 

 a heavy rain. No further details are available on this case. 



In a recent number of the Avicultural Magazine (vol. 53, 1947, 

 p. 104), it was announced that the Avicultural Society of South 

 Australia had awarded its medal in 1937 to C. C Cosgrove for breed- 

 ing black-^vinged combassous in his aviary. Through the kindness 

 of Phyllis Barclay-Smith and Alan Lendon, I contacted Cosgrove. 

 He informed me that his combassous were raised by a pair of fire 

 finches in the aviary. His first indication of the young combassous 

 came when they were already independent of parental (or foster 

 parental) care. About 5 weeks later he noted a male fire finch feeding 

 a young bird different from its own. He then discovered a pair of 

 fire finches feeding three young birds, which, when they reached 

 maturity turned out to be black-winged combassous. 



Olsen (1958) reported what amounts to a dual case. In his aviary 

 in Denmark, a young black-winged combassou was reared in 1956 by 

 a pair of fire finches. The following year this combassou, which 

 turned out to be a hen, mated with its father and layed two eggs in a 

 nest of the same host, together with three eggs of the latter. One 

 young combassou and two fire finches were reared from tliis nest. 

 Olsen reported that the female fire finch began to incubate on July 20 

 and that all the eggs hatched on July 31, the period of incubation 

 amounting to 11 days and being the same for both the host and the 

 parasite. The parasite had no accelerated developmental gi'adient as 

 occurs in some brood parasites. The young of both species left the 

 nest on August 18, the nestling period amounting to 18 days. 



We have, then, two reports (Russ and K. Nielsen) that suggest a 

 certain amount of nest building (or at least the picldiig up and carry- 

 ing of nesting materials), and of care of the young, (possibly also 

 incubation) by combassous in a state of captivity. One of these 

 (Russ) is less definite than the other. Contrasting with them are at 

 least five reports (Boyd, Cosgrove, A. Nielsen, Olsen, and Tomlin- 

 son) of parasitic breeding. These reports agree with what is known 

 of the habits of the various species of combassous in the wild state. 

 The only conclusions that I draw are that these birds are brood para- 

 sites and that the two supposedly contrary instances are not as com- 

 pletely established as their reporters seemed to think. True, years 

 ago A. G. Butler (1914b) wrote that combassous in his aviaries built 

 in any of the usual nesting receptacles placed there, but he never 

 reported any details and never succeeded in raising these birds. He 

 attributed his failure to the fact that his hens generally died from egg 

 binding, but his observations were not recorded and therefore do not 

 constitute data. The facts, which seem acceptable, that the adult 

 male combassou feeds the fledged young birds and that the adult male 



