OBSERVATIONS ON THE CUCKOO. 59 
cient reasons for believing that both these extremes 
are erroneous. According to Montagu*, whose opi- 
nion is founded on the dissection of breeding females, 
Cuckoos lay from four to six eggs; and this is pro- 
bably near the truth. In females opened when they 
had just begun to lay, only four or five eggs were 
usually discovered that could possibly be laid in suc- 
cession, from the smallest of which to what may be 
termed the secondary eggs there was a sudden break 
off, not a gradual decrease in size. ‘The scarcity 
also of the eggs and young of this species, even in its 
favourite haunts, tends powerfully to confirm the 
opinion that Dr. Jenner has greatly overrated its 
fecundity f. 
It is possible that those Cuckoos which arrive early 
may sometimes lay two sets of eggs during their stay 
with us; but then we may safely conclude that a 
considerable interval of time always elapses between 
the production of the first and second sets; and it 
is quite as probable that those eggs which are occa- 
sionally found in July should be laid by birds which 
arrive late, as by early-coming birds which produce 
* ¢ Ornithological Dictionary,’ Introduction, p. 8 and follow- 
ing. 
+ White Moss, a bog of considerable extent, situated about 
four miles to the N.E. of Manchester, is a very favourite resort 
of Cuckoos; yet the turf-cutters inform me that even in the 
most favourable seasons they never knew of more than five or 
six eggs belonging to this species in different nests at the same 
time. 
