THE VOYAGE OF THE BEAGLE 307 



of some lofty tree the indistinct but plaintive note of the 

 white-tufted tyrant-flycatcher (Myiobius) may be noticed. 

 From the great preponderance in most countries of certain 

 common genera of birds, such as the finches, one feels at 

 first surprised at meeting with the peculiar forms above enu- 

 merated, as the commonest birds in any district. In central 

 Chile two of them, namely, the Oxyurus and Scytalopus, oc- 

 cur, although most rarely. When finding, as in this case, 

 animals which seem to play so insignificant a part in the great 

 scheme of nature, one is apt to wonder why they were 

 created. 



But it should always be recollected, that in some other 

 country perhaps they are essential members of society, or 

 at some former period may have been so. If America 

 south of 37 were sunk beneath the waters of the ocean, 

 these two birds might continue to exist in central Chile for 

 a long period, but it is very improbable that their numbers 

 would increase. We should then see a case which must in- 

 evitably have happened with very many animals. 



These southern seas are frequented by several species of 

 Petrels: the largest kind, Procellaria gigantea, or nelly (que- 

 brantahuesos, or break-bones, of the Spaniards), is a com- 

 mon bird, both in the inland channels and on the open sea. 

 In its habits and manner of flight, there is a very close re- 

 semblance with the albatross; and as with the albatross, a 

 person may watch it for hours together without seeing on 

 what it feeds. The " break-bones " is, however, a rapacious 

 bird, for it was observed by some of the officers at Port St. 

 Antonio chasing a diver, which tried to escape by diving 

 and flying, but was concinually struck down, and at last 

 killed by a blow on its head. At Port St. Julian these great 

 petrels were seen killing and devouring young gulls. A sec- 

 ond species (Puffinus cinereus), which is common to Europe, 

 Cape Horn, and the coast of Peru, is of much smaller size 

 than the P. gigantea, but, like it, of a dirty black colour. It 

 generally frequents the inland sounds in very large flocks : 

 I do not think I ever saw so many birds of any other sort 

 together, as I once saw of these behind the island of Chiloe. 

 Hundreds of thousands flew in an irregular line for several 

 I hours in one direction. When part of the flock settled on the 



