120 



Dealing with the theory of dimorphism, as illustrated by this species, Captain Hutton says: 



If we reject the idea of dimorphism as improbable, and that of change due to age as disproved, we have 

 three different hypotheses to chose from to explain the facts : 



1. — Two distinct species, sometimes producing hybrids. 



2.— One excessively variable species, one form producing, in an irregular way, the other. 



3.— Two species developed by ordinary variation going on for a long time, while the intermediate forms 

 have not become extinct. . . . 



For my part, I strongly incline to the last hypothesis, which is more in accordance with what we know 

 m other cases, and, as I think, offers the best explanation of the facts as at present known. For I cannot but 

 think that (E. neglecta and (E. phillipi are two closely related species, while (E. neglecta, var., is an incipient 

 species, which perhaps does not always breed quite true. 



It is doubtless of this species that a newspaper correspondent gives the following interesting 

 account : 



In countless thousands they reach their breeding ground in Phillip Island and the neighbourhood, on the 

 eastern coast-line of Victoria, within a few hours of the same date every year. Some idea of the gregarious- 

 ness of these birds is given by Captain Waller, of the ' Westralia. He states that on one occasion, while on 

 the journey between New Zealand and Australia, he steamed for thirty miles through solid flights of Mutton- 

 birds, extending to a distance of three or four miles on each side of the vessel. Occasionally they settled on 

 the water, and when they did that they covered the surface and looked like a reef of black rocks. They were 

 on their way to the Victorian coast, to occupy their nests on the land. 



Order PEOCELLAEIIFOBMES.] 



[Family PUFFINID7E. 



OSSTEEAGA GIGANTEA 



(GIANT PETEEL.) 



Ossifraga gigantea (Gmelin), Duller, Birds of New Zealand, vol. ii., p. 225. 



In my budget of ornithological notes communicated to the Wellington Philosophical Society on 

 October. 21st, 1891, I said: "Of this fine Petrel, several remarkable examples have lately come 

 under my notice. The specimen exhibited, which is an almost pure albino, was captured a few 

 weeks ago off the coast near Kaikoura. The general plumage is white, but there are widely 

 scattered feathers of the normal colour. There is a similar specimen in Mr. S. W. Silver's fine 

 collection of New Zealand birds at Letcombe Eegis, near Wantage. There is on board the 

 ' Hinemoa ' the skin of another which was shot by the chief steward, off the Snares, about a year 

 ago. In this the dark feathers are fewer, or more widely scattered, and the bill is of a 

 yellowish horn-colour. Captain Fairchild tells me that for a long time past he has observed 

 a perfectly white one at the Bounty Islands: but it is a very shy bird, and hitherto has 

 kept well out of gun-range." 



Since the above was written I have received another beautiful albino which was shot at sea 

 about ten miles north of Milford Sound. 







