AVIAN GENUS CHRYSOCOCCYX 73 



by those of others dealing with still different hosts. Thus, a record by 

 Bell-Marley (in Friedmann, 1949a, p. 136) involving the amethyst 

 sunbu'd and another by Roberts (1940, p. 143) concerning a parasitized 

 nest of the paradise flycatcher showed similar discrepancy in appear- 

 ance of the eggs of the parasite and of its hosts. On the other hand, 

 Pitman himself (1957, pp. 3-6) wrote that at Entebbe, Uganda, the 

 sunbirds, Nectarinia erythroceria and Chalcomitra senegalensis, were 

 common hosts. "The eggs of both . . . species are generally dark 

 brownish in appearance, and the eggs of C. klaas are likewise. . . ." 

 Again, Pitman {in Hit.) summarized much of his experience with eggs 

 of klaas in Uganda by describing them as resembling to a fair degree 

 the eggs of some of the commonly used hosts, particularly in their 

 densely speckled pattern. 



The eggs of klaas are much like those of caprius in their variable 

 color patterns but are smaller in size and, in general, somewhat more 

 slender. According to Pitman, the eggs of klaas are "tougher" than 

 those of either caprius or cupreus. Eggs of klaas vary in size from 15.2 

 to 19.5 mm. in length and from 11.4 to 12.6 mm. in ^^^dth. The larger 

 measurements in my earlier account (1949a, p. 137) now appear to 

 have been of caprius eggs misidentified as klaas in the literature. 



Egg measurements (in mm.) given by Schonwetter (1964, p. 586) 

 are as follows: length 18.9 (16.9-20.0); width 12.8 (12.1-13.5); weight 

 of empty shell 0.10 (0.08-0.11) grams; thickness of the shell 0.07; 

 weight of full egg 1.65 grams; relative weight of shell to weight of full 

 egg 6.1 percent. 



The kno^vn eggs of klaas are all of the nominate race. 



8. C. cupreus: apparently polymorphic, but only a small number of 

 eggs are known; these may be divided into four types: 1. white, either 

 immaculate or with a few purplish flecks forming a loose wTcath at 

 the obtuse pole. 2. white or cream, very thickly speckled with olive- 

 browTi, found in nests of olive smibird by Benson & Benson (1947, 

 p. 4) in Nyasaland and by Moreau in Tanzania; this egg type agrees 

 fairly well with those of the host. 3. pale pinkish to pinkish white, 

 spotted with brown and gray, "similar to those of Pycnonotus, but 

 smaller . . ." (van Someren, 1956, p. 159) ; found in nests of the bulbul, 

 Pycnonotus barbatus, in Kenya. 4. pale blue (in collections, faded 

 afterw'ard to white), described by Schonwetter (1964, p. 568). 



In spite of the meager quantity of evidence, there is reason for 

 interpreting as "probable" some adaptation in egg coloration to at 

 least two hosts, the yellow-vented bulbul, Pycnopotus barbatus, and 

 the ohve sunbird, Chalcomitra olivacea. The eggs of the parasite are 

 smaller than those of the bulbul, but larger than those of the sunbird. 

 The bulbul is the most frequently recorded host of the emerald 



