The Oologisis' Record, September i^ 1922. 63 



The Hobby almost invariably chooses for its eyrie the disused 

 nest of a Carrion Crow-^preferably one of the year from which 

 either the eggs have been removed earlier in the season or the young 

 have flown. No alteration or preparation whatever is made in such 

 nest, although it has been confidently asserted by -some observers 

 that the lining of wool is entirely removed. In the event of an 

 older nest being occupied, from which the wool from various causes 

 has disappeared, the hollow may be slightly rounded, but no addi- 

 tion of any kind is made. 



I have on three occasions found the nest of the Hobby in an 

 inhabited rookery. 



The site chosen is nearl}^ always one which commands a wide 

 outlook over open country, and a clump or belt of trees is preferred 

 to a large wood. When in the latter, the nest is usually on or close 

 to the edge or in a clearing. I have never personally found one in 

 the middle of a wood, although I am aware that such have very 

 occasionally been recorded, and I know a district in Gloucestershire 

 where the single pair of Hobbies almost invariably occupy a nest in 

 a hedgerow elm or oak in a quiet valley. 



The Hobby seldom has a full set of eggs before June 19 — often 

 not until June 30, or even the first few days of July. I have, 

 however, once found a set on June 12, but I consider this to be 

 exceptional. 



Should the first eggs be taken, the Hobby will very exceptionally 

 lay a second time. I have indisputable evidence of this ; but 

 careful observations taken over a number of years have tended to 

 make me a little sceptical as regards the percentage of birds which 

 do so. 



In England the normal clutch of eggs is three. I have once 

 seen four, and I am informed that another well-known authority has 

 had a like experience ; these are the only recorded instances. 

 Clutches of two, however, are not infrequent. The eggs vai"y con- 

 siderably in size ; they are generally larger than those of the Kestrel, 

 but often smaller. There is an appreciable variety in the colouration 

 of individual clutches, but as a general rule eggs of the Hobby are 

 unmistakable, notwithstanding anything that may have been stated 

 to the contrary. 



The behaviour of individual pairs of Hobbies at the nest varies. 

 At certain times of the day the cock is generally to be found at rest 

 in a tree close to the nest, leaving when an intruder is some distance 



