GREY CUCKOO. 115 



In examining a female I found not less than twelve eggs 

 that were in the progress of development. They were disposed 

 in separate clusters, one of which contained three, another six, 

 and the third three. One of them had a diameter of nearly 

 five twelfths of an inch, and therefore was ready to pass into 

 the oviduct, which was of course highly developed and curious- 

 ly contorted ; the inner surface of its upper part longitudinally 

 rugous, the lower transversely and spirally. This observation 

 is of course decisive as to the Cuckoo's laying more than one 

 egg in the season, or at a time. Fig. 6 represents the parts in 

 question : a, the eggs ; b, the oviduct, entering into the cloaca, 

 c. Fig. 7 shews the internal surface of part of the oviduct cut 

 open. From the size of the oviduct it would appear that one 

 or more eggs had already been laid, and it is probable that the 

 bird continues to lay at intervals from the middle of May to 

 near the period of its departure ; for INIontagu states that he 

 found a fully developed egg in one shot on the 26th of June. 



The stomach is so large that when distended it almost en- 

 tirely fills the anterior or lower part of the abdomen, with the 

 walls of which it is in contact ; and this circumstance has been 

 adduced as furnishing a reason for the parasitic habits of the 

 species, it being imagined to prevent incubation. But in many 

 other birds, the Owls and Goatsuckers, for example, the sto- 

 mach is similarly situated, and equally large. Indeed, the 

 connection of the two facts is merely one of the many hundreds 

 of false reasonings with which natural history is encumbered. 

 The coeca, as I have already mentioned, vary in size, and are 

 generally unequal, the left being smaller. Fig. 8 represents 

 those of another individual. 



Habits. — The Cuckoo arrives in the south of England about 

 the 20th of April, in the south of Scotland towards the end of 

 that month, and in the northernmost parts of Britain soon after 

 the beginning of JSIay. The periods of arrival, however, vary 

 considerably according to the character of the season, and as 

 the birds do not always announce their return by emitting their 

 well-known cry, they may sometimes be met with at a time 

 when their presence is not suspected. There seems to be hardly 



