NO. 4 AVIAN GENUS CLAMATOR — FRIEDMANN 47 



The high incidence of multiple eggs in Clamator glandarius, par- 

 ticularly in sub-Saharan Africa, raises the question as to the situation 

 in the other members of the genus. A summary of all the available 

 data gives the following figures, none of which comes up to those 

 we have just considered. 



Clamator coromaudus 



Baker's (1942, p. 152) data on 171 nests containing 225 eggs of 

 this cuckoo reveal 171 were singles when laid, and 54, or 31.5 percent 

 were multiples. Of the parasitized nests 139, or 81.3 percent had 1 

 cuckoo tgg apiece, and 32, or 18.7 percent had been parasitized more 

 than once. 



Clamator jacobinus 



Data on 220 nests containing 290 eggs of this species show 220 

 were singles when laid, and 70, or 24 percent, were multiples. Inas- 

 much as this is a species which has extended its range (from Africa 

 to Asia) and is, in this regard, somewhat comparable to C. glan- 

 darius, we may treat the Asiatic separately from the African data. 



Asia: 106 nests containing 142 eggs, of which 106 were singles 

 when laid, and Z6, or 25 percent, were multiples. Of the 106 nests 

 parasitized, 84, or 78.2 percent, had but a single cuckoo tgg each ; 22, 

 or 21.8 percent, had been parasitized more than once. 



Africa: 114 parasitized nests were found containing 152 eggs, of 

 which 114 were singles when laid, and Z^, or 25 percent, were mul- 

 tiples. Of the 114 nests, 98, or 86 percent had a single cuckoo egg 

 each, and 8, or 14 percent had been parasitized more than once. 



We may point out that the absence of any significant difference 

 in the ratio of multiple-egg deposition in the two great segments of 

 this species is decidedly different from the comparable picture in the 

 great-spotted cuckoo. It adds one more support to the contention 

 that the great geograpliic spread of glandarius and of jacobinus 

 were, in an evolutionary sense, quite opposite of each other. In the 

 former species it was a very recent (late) advance after a high evolu- 

 tionary development had been achieved ; in the latter species it was an 

 early spread prior to the evolution of egg adaptation. In glandarius 

 the geographic "advancers" still reveal a lesser degree of efficiency 

 in their host relationship than do their "stay-at-home" ancestors; in 

 jacobinus this is not true. Of the total 220 nests parasitized by the 

 latter species, throughout its range, 182 contained 1 egg each of the 

 cuckoo, 21 had 2, 9 had 3, 5 had 4, 2 had 6, and 1 had 7. 



