Egg Coloration in the Cuckoo, Cuculus canorus. 107 
is common, e.g. Meadow Pipit. But it must be admitted that this view is 
open to criticism similar to that suggested above. As regards the foster 
species considered in this paper, all that the evidence may safely be claimed 
to show is that while a bias towards a particular haunt, eg. a river bank, 
may be exhibited by a Cuckoo, the choice of species for foster 
parents within that haunt would appear to be determined more by the 
frequency of occurrence of its nests, or the facility with which the 
nests are discovered by the Cuckoo, than by any hereditary bias towards 
a particular foster. 
LITERATURE CITED. 
1. Batpamus, A. C. E. Das Leben der ewropiischen Kuckucke, Berlin, 1892. 
2. Herrick, Francis H. Jour. Hxp. Zool., 9, 1910, p. 169. 
3. Latter, O. H. Biometrika, vol. 4. 
4. Newton, A. Dictionary of Birds. 
(Issued separately, 14th February 1914.) 
