NOTES AND QUERIES. 147 
but that these three Cuckoo's eggs had been laid by one bird. If this be 
So, it strengthens the idea that each female Cuckoo probably lays its eggs 
only in the nests made by one species of bird. It seems probable, too, that 
a Cuckoo reared in, say, a Whitethroat’s nest would by-and-bye lay its eggs 
in Whitethroats’ nests; and that Whitethroats’ nests would be selected by 
a sort of hereditary instinct. Dr. Baldamus, if I remember correctly, 
thought that the Cuckoo when about to lay was influenced by the colour of 
the eggs in the nest before it; and that in consequence its eggs assimilated 
in colour to those already laid by the owner of the nest. If there be anything 
in such colour assimilation, would not the fact I have above recorded suggest 
that it may in part be due to gradual and hereditary influence ?—A. B. 
Farn (Fairlawn, Stone, Dartford). 
Edible Birds’ Nests.—The Alga of microscopic dimensions found by 
Mr. Pryer in the cave inhabited by the Swifts which build the edible 
nests (noticed by him, pp. 43—50), is an undescribed species of Uro- 
coccus. ‘The members of the group to which it belongs are very com- 
monly found growing on the walls of caverns. In this case the incrustation 
produced by the accumulation of the Alge is of unusual thickness and of 
horny consistency when dry, but turns pulpy when soaked in cold water. 
On the outer surface there is a dark layer (black to the naked eye, but very 
dark greenish yellow when viewed with the microscope), consisting of the 
living Algw. Beneath this outer dark layer the mass of the incrustation 
is white, and consists of a dense accumulation of innumerable dead bodies 
of the Algz, the structure of which is barely distinguishable. In none of 
the edible nests which I have examined, however, is there any trace of an 
Alga, and it appears to be definitely settled that these are constructed 
from materials which are the intrinsic product of the bird. Mr. Pryer 
states his opinion that certain nests are made from the black outer layer of 
the incrustation. If such a nest were examined it would give conclusive 
evidence either way, since the black layer, as just mentioned, consists of 
living Algz, the structure of which would be far more readily discernible 
than the traces of the white part of the incrustation—Grorez Murray 
(British Museum, Natural History). 
Red Grouse in Somerset and Wilts. —I have ascertained from 
Mr. Edwards, of Wrington,—who informed me of the occurrence of the 
Red Grouse near that place (as recorded by me, p. 66),—the following 
particulars, which may be of interest to Mr. Cambridge Phillips and others 
of your readers. In answer to some questions which I] put to him in 
consequence of Mr. Phillips’s note, Mr. Edwards writes :-—« The bird was 
alone. The hill on which I killed it [one of the Mendips] is about 1500 
acres in extent, and the highest point about 1064 feet, according to the last 
Ordnance Survey. I should estimate the extent of heather at about 200 
