PELECANOIDES EXSUL. 



itself, and the other from the Auckland Islands (p. 439). Here P. exsul meets the 

 range of P. urinatrix, and the question arises whether they are really distinct 

 species. The latter, it is true, has a white throat, while that of the Kerguelen bird 

 is grey, but it has yet to be proved whether these differences of plumage are not 

 due to age, season, or mere variation. Dr. Reichenow unites the two forms in his 

 most recent Memoir (Deutsche Siidpolar Exped., IX., Zool., I., p. 558). 



Notes on the breeding of P. exsul, on Kerguelen Island, have been published 

 by the late Professor Moseley, the Rev. A. E. Eaton, Dr. Kidder, and Mr. Robert 

 Hall, and from them we learn that during calm weather, large flocks are sometimes 

 seen which cover acres in extent, so that the surface of the sea is black with the 

 birds. Dr. Kidder states that a single white egg is laid in a burrow on the hillside, 

 generally in the same locality as that of Halobcena ccerulea, but the nesting-tunnel 

 is shorter. 



When the British " Transit of Venus ' J Expedition reached Kerguelen Island, 

 the Diving Petrels had already begun to pair, and the Rev. A. E. Eaton records 

 the first egg as taken on the 31st of October. Before it was laid both birds were 

 to be found in the nesting-chamber, making a moaning noise during the daytime. 



It should be noted that Mr. Nicoll, when describing the bird from Tristan da 

 Cunha under the name of Pelecanoides dacunhce, noticed some difference in habit 

 and mode of flight as compared with that of other Diving Petrels, which he had seen 

 in the Straits of Magellan, and which were doubtless P. urinatrix. Superficially the birds 

 were alike, but P. dacunhce seemed to be much smaller, and to have a considerably 

 greater power of flight. On several occasions he saw the birds rise off the water, and 

 fly out of sight, whereas the species of the Magellan Straits would drop again after a 

 short flight of about fifty yards. The Diving Petrels of Tristan da Cunha are exposed 

 to rough weather and breaking waves, and have, in consequence, continually to take 

 wing to avoid being drowned, and this fact may account for their greater powers of 

 flight. On leaving the " Valhalla " in pursuit of specimens, Mr. Nicoll met with 

 his P. dacunhce, which became more numerous as he approached the land. Half 

 a mile from the shore the birds were on all sides of the boat, continually 

 appearing close to it, but instead of diving again, they at once took flight, and 

 disappeared at great speed (Nicoll, Voy. Nat, p. 68). 



The Rev. A. E. Eaton, who was naturalist to the British " Transit of Venus " 

 Expedition, alludes in his notes to the remarkable resemblance of the Diving Petrels 

 to the Little Auk (Mergulus alle) of the Northern Hemisphere. The Auk, however, 

 during the breeding season usually flies and fishes in small flocks, consisting of six or 

 more birds, and nests in communities of considerable size, which are exceedingly 

 noisy. Diving Petrels, on the other hand, fish and fly for the most part in pairs, 

 and nest sporadically. 



The burrows on Kerguelen Island were about the size of those of the English 



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