152 U.S. NATIONAL MUSEUM BULLETIN 223 



were probably laid by paradise widow birds. In another publication 

 (1930b, pp. 73-75), he devoted himself explicitly to this question, 

 and gave details and photographs of several parasitized sets of melba 

 finch and of yellow-backed pytilia eggs, all taken in Nyasaland. In 

 his account of the birds of the Belgian Congo, Chapin (1954, p. 510) 

 agreed that there "is good reason to believe that the eggs of Steganura 

 paradisaea are frequently deposited in the nests of Pytilia melba, 

 where they can be distinguished by their larger dimensions." Prob- 

 ably on the basis of these still far from certain records, Mackworth- 

 Praed and Grant (1955, pp. 1049-1050) merely stated that the 

 paradise widow bird is parasitic on species of the genus Pytilia. 



Despite all these statements, we still lack conclusive proof that 

 the melba finch is a host of the paradise widow bird. In captivity 

 aviculturists have recorded incontrovertible instances of this actually 

 happening, but in these cases the paradise widow bird was necessarily 

 limited to the birds breeding in the same cages. A. L. Robertson 

 (1946, p. 209), gave the following information: "In captivity this 

 bird has parasitized the nest of Melba finches and in 1943 and 1944 

 they were successfully bred by two independent people. . . . After 

 the first nest of Melba finches had been successfully reared along with 

 two paradise whydahs, I examined other nests of Melba finches and 

 found eggs white in colour and slightly larger than the Melba finch 

 eggs. The Paradise Widow hens not only parasitized Melba finch 

 nests but also deposited eggs in Australian Zebra Finch nests as well. 

 [This parasitism, of course, could only happen in an aviary. 1 In all, 

 in one breeding season, four young Paradise Widow Birds were bred. 

 The following year in Pretoria they were again successfully bred and 

 the host again was a Melba finch." In a later paper, A. R. Robertson 

 (1949, pp. 158-159) gave details that transpired in an aviary of 

 Prinsloo at Evaton, Transvaal. In a cage about 24 by 12 by 8 feet, 

 there were among other birds three pairs of melba finches, and two 

 male and one female paradise widow birds. The three pairs of melba 

 finches nested at different times during the season, but each time 

 the nest was parasitized by the female paradise widow bird. 



During the course of the incubation period by the first Melba hen it was noticed 

 that the Paradise hen paid visits to the . . . nest. . . . Three 3'oung ones left 

 the nest, two were Melbas . . . but the third . . . was not. . . . As it grew 

 older and was able to fend for itself it left the Melbas and was to be found only 

 with the Paradise Whydahs which it now resembled very closely. When the 

 second Melba Finch went to . . . nest I examined the eggs; there were six in all. 

 Five were almost identical and white, and, I presumed, Melba eggs, the sixth egg 

 white as well, but larger and longer than the other eggs. From this nest eventually 

 one Paradise Whydah was reared. The Paradise Whj'dah did not only confine 

 her marauding to the nest of Melba Finches, but laid eggs in the nests of every 

 Australian Zebra Finch she could find. 



