Collection of Birds from the Mediterranean. 177 



The rocky islet on wliicli tlie Falcons breed is 1^ acres in 

 extent, about lialf its edge is precipitous, and the brittle 

 limestone of which it is composed is honeycombed every- 

 where with large and small holes, providing suitable nesting- 

 sites for Cormorants {Phalacrocorax graculus ?) and Gulls 

 [Lams cachitinans and possibly also L. audouini, an example 

 of which was seenclose by), but their nests had of course 

 been tenaniless for some months. 



The Falcons^ nests were not confined to the precipitous 

 parts — indeed only two out of the ten found needed a rope 

 to get at them. Five nests were quite on the top of a 

 detached peninsula with perpendicular sides, the eggs being 

 placed in '' pot-holes" among the limestone facets. One 

 clutch of three eggs was placed in a Cormorant's old nest. 



There seemed to be at least twelve pairs breeding in the 

 islet, which abounded with the remains of freshly-killed 

 birds, chiefly Wrynecks and Hoopoes, the autumn migra- 

 tion being in full progress and small birds abundant in 

 consequence. 



Only one of the nests contained young birds (three in 

 number), the remainder had eggs (3, 3, 3, 3, 3, 2, 2, in 

 number), averaging ten days of incubation. Two clutches on 

 the flat top had been broken recently, possibly by fishermen 

 who sometimes go th.ere. In two of those with three eggs, 

 one of the eggs was separated about eight inches from the 

 others, as though it had been deliberately put aside so as not 

 to hatch. Certainly in one case, and probably in the other, 

 the embryo was dead. 



To lay three eggs would seem to be the rule, but not to 

 rear more than two young, for in all nests with three eggs 

 one was addled (in one nest two). The parent bird sat very 

 close on the nest of two young (each about two days old). 

 The broken shells of the eggs were just thrown out of the 

 nest and were lying two feet away. Two of them pieced 

 together almost perfectly. In the nest were three castings, 

 two of small birds and one of beetle-remains. 



All other nests (with the eggs) were void of food except 

 one, close to which were the remains of a Roller, the leg of 



SER. IX. VOL. VI, N 



