VOL. XIII. NESTING OF STORM-rETREL. 



233 



one could make out in the uncertain light, the birds uttering 

 this cry did not fly out to sea, but simply circled round the 

 nesting area, at a great pace, like nocturnal Swifts. It is 

 probable that this flight, accompanied by this queer cry, forms 

 the display of the cock bird, and while it is going on, the hen 

 bird remains in the rocky crevice and keeps up an incessant 

 " purring." The period of greatest activity was about 2.30 



STORM-PETREL WITH YOUNG ABOUT 3 DAYS OLD. 



(Photographed by Mrs. Gordon.) 



a.m G.M.T. As soon as it began to get lighter, the Petrels all 

 returned to their holes, the activity ceasing very abruptly, 

 but they continued " purring " for some time longer. On 

 one occasion, at night, I disturbed a pair of Petrels close 

 together on an open ledge of rock, both " purring." Possibly 

 mating was taking place. 



None of the eggs were hatched by July 15th, but most of 

 the birds had laid by that time. 



