OF SELBORNE. 155 
and I saw, at the time mentioned, many hundreds 
of young wagtails on the banks of the Cherwell, 
which almost covered the meadows. If the matter 
appears as you say in the other species, may it not 
be owing to the dams being engaged in incubation, 
while the young are concealed by the leaves? 
Many times have [ had the curiosity to open the 
stomach of woodcocks and snipes; but nothing 
ever occurred that helped to explain to me what 
their subsistence might be; all that I could ever 
find was a soft mucus, among which lay many pel- 
lucid small gravels. 
LETTER IV. 
Selborne, Feb. 19, 1770. 
Dear Sir,—Your observation that “ the Cuckoo 
does not deposite its egg indiscriminately in the 
nest of the first bird that comes in its way, but 
probably looks out a nurse in some degree con- 
