DIVING PETRELS. 89 



applies : " Carefully watching the lirds flying to and fro about the rocks, we observed 

 that they occasionally disappeared into crevices amongst piles of loose stones, and 

 crept under loose masses of rock. Having meanwhile ascertained their call, we were 

 able, by listening attentively, to detect the exact positions of several of these hidden 

 birds. They were easily caught when the stones were rolled aside ; but they were in 

 couples, merely preparing for laying, and therefore we did not find any eggs." It 

 may be remarked that the petrels usually are found in pairs in the holes before the 

 breeding commences. Later, only one of the parents occupies the nest, while the other 

 one brings food to the breeding mate during the night; after the chick is hatched, 

 both parents stay away during the day, only visiting and feeding it after dark. " The 

 egg," Mr. Eaton continues, " is laid upon the bare ground, within the recess selected 

 bv the birds, either in a chance depression formed by contiguous stones, or in a shallow, 

 circular hollow excavated in the earth by the parent. Having found numbers of their 

 nesting-places I will describe my method of searching for them. Whenever there was 

 a calm night, I used to walk with a darkened bull's-eye lantern towards some rocky 

 hillside, such as the petrels would be likely to frequent. It was best to shut off the 

 light and keep it concealed, using it only in dangerous places where falls would be 

 attended with injury, and progress in the dark was hardly possible, lest the birds, see- 

 ing it, should be silenced. On arriving at the ground selected, it was probable that 

 storm petrels would be heard in various directions, some on the wing, others on their 

 nests, sounding their call at intervals of from two to five minutes. Those on nests 

 could be distinguished from others flying, by their cries proceeding from fixed posi- 

 tions. Having settled which of the birds should be searched after, a cautious advance 

 had to be made in her direction, two or three steps at a time, when she was in full 

 cry. As soon as she ceased, an abrupt halt was imperative, and a pause of some min- 

 utes might ensue before she recommenced her cry and permitted another slight 

 advance to be effected. In the course of this gradual approach, the position of the 

 bird might be ascertained approximately; but it had to be determined precisely, and 

 to learn exactly where she was, she had to be stalked in the dark noiselessly. No gleam 

 could be permitted to escape from the lantern. Loose stones, and falls over rocks, - 

 to avoid them it was sometimes necessary to dispense with slippers, and feel one's way 

 in stockings only, for should the petrel be alarmed once with the noise or the light, 

 she would probable remain silent a considerable time. ISTow and then it would happen 

 that, upon the boulder beneath which she was sitting being almost attained, the bird 

 would cease calling. When this occurred, and many minutes elapsed without her cry 

 being resumed, it was advisable to make a detour, and approach the rock from the 

 opposite side, as her silence might be attributed to her seeing a person advancing 

 towards her, and she would probably recommence her call as soon as he was out of 

 sight. If she did not, a small pebble thrown amongst the rocks would usually elicit 

 some sounds from her, as she would most likely conclude that the noise was being 

 made by her mate returning to the nest. When the stone beneath which the bird 

 was domiciled was gained at last, redoubled care had to be exercised. By 

 stooping down, and listening very attentively, her position could be accurately 

 ascertained. Then the lantern was suddenly turned upon her before she had time to 

 creep out of sight, and her egg could be secured with the hand, or with a spoon tied 

 on to a stick." 



Among the Procellariinas several groups may also be distinguished : first, the 

 small stormy petrels, 'Mother Carey's chickens.' as they are usually called. 



