458 Observations on the Cuckoo. 
The following Table exhibits the mean 
weight of the cuckoo, and of several birds 
in whose nests it most frequently lays: also 
the mean weight of their eggs, with the ratio 
of the weight of each bird to that of its egg, 
omitting fractions, 
TABLE. 
| amps. seine @ a preneasy rg tothe pang 3 
1 SLA ees tag ot Seria (eS 
ICuckoo Seecebi lacs 2297 55 oe 
Titlark ....se0ee : 289 35 + 
Lesser Fieldlark 354 37 Z 
Yellow Bunting 412 43 + 
_|Hedge Warbler 332 35 2 
Pied Wagtail ... 333 37 eS 
If it be admitted, as I believe it safely may, 
that cuckoos lay from four to six eggs, it will 
not be difficult to furnish data from which a 
rude estimate may be made of the mean an- 
nual destruction occasioned by young cuckoos 
among small birds in England and Wales. 
Early in May, before cuckoos have begun to 
breed, and before the foliage of forest trees 
has been sufficiently expanded to afford them 
shelter and concealment, I have known nine 
or ten of these birds come in an evening to 
roost among the evergreens in the plantations 
a a a 
