203 ]\Iajor R. F. Meiklejolm on the [Ibis, 



(h) III some districts on the Coatinent the eggs of the 

 Cuckoo are almost invariably of the same type as those of 

 the most abundant species, and consequently that which is 

 most often selected as foster-parent. Amongst many eggs 

 recorded by Rey from the Dessauer Heide and northern 

 Finland not a single one differed from the Redstart type, 

 and in these localities that species is almost invariably 

 selected as foster-parent ; whereas in Lapland, where the 

 e2,gs are practically always deposited in nests of tiie 

 Brambling, a very large percentage resemble the type of 

 that species. Further, according to " Westfalen's Thier- 

 lebeu'^ (ii. 20), Cuckoos' eggs from the moors of Oldenburg 

 always resemble the type of the Meadow-Pipit, the usual 

 foster-parent in that locality. 



(c) In other localities, on the contrary. Cuckoos' eggs are 

 often found in the nests of species they wezr^r resemble, such 

 as those of the Wren or Willow-Warblers. Walter found 

 over 150 specimens in nests of the Wren, yet, according to 

 his observations, this species, and the Willow-Warblers also, 

 invariably desert their nests in consequence, as the Cuckoo 

 in depositing her egg enlarges the entrance-hole and damages, 

 the nest. 



{d) In Britain the Hedge-Sparrow is frequently selected 

 as foster-parent, and the eggs are, as a rule, successfully 

 hatched. Yet Cuckoos^ eggs found in the nests of this 

 species are never blue, and Rey says this is also the case oa 

 the Continent. 



(e) The eggs of the Cuckoo vary more in colour and mark- 

 ings than those of any other known species. The ground- 

 colour ranges from white, yellowish, greyish, or violet-grey, 

 to greenish, bluish, brownish, reddish, etc., and the mark- 

 ings, which at times are clearly defined, or at times shade 

 into the ground-colour at the edges, are blotches, spots, 

 or scrolls of black, brown, yellowish, ashy-grey, reddish, 

 reddish-brown, violet, greyish-green, etc. As a rule they 

 are most profuse round the larger end and form a zone. 

 Some specimens are uniform bluish-green or blue, with,, 

 at times, a few faint spots of rusty-red. 



