2 EINAR LONNBERG 
Breeding sea birds (6 sp.) 
Fregetta grallaria 
Puffinus creatopus 
Pterodroma neglecta 
( » externa) Pterodroma externa 
» defilippiana » masafuerae 
Accidental visitors: 
A. Migrants from the north (3 sp.): 
Asio flammeus Buteo obsoletus 
Crymophilus fulicarius 
B. Visitors from the South American continent (5 sp.): 
Belonopterus chilensis — Haematopus ater 
Cathartes sp.? Circus maculosus 
Cygnus melanocoryphus 
C. Roving sea birds (5 sp.): 
Priocella antarctica (= glacialoides) 
Daption capensis Daption capensis 
Diomedea melanophrys 
Spheniscus magellanicus 
> humboldti 
Introduced by man (2 sp.): 
Columba livia Columba livia 
Lophortyx californianus 
Uncertain: 
Eustephanus leyboldii 
The indigenous land birds are partly endemic species (Anaeretes fernande- 
zianus, Aphrastura (Oxyurus) masafuerae, and the remarkable Eustepbanus fer- 
nandensis) which have their nearest relatives on the neighbouring continent, 
partly identical with continental species, although in some cases they have 
differentiated through isolation into separate races. Of the sea birds, Ptero- 
droma externa, defilippiana and masafuerae have been found breeding only on 
these islands, thus being entitled to be listed as endemic species, or, at least, 
as local races, not quite identical with such breeding on other islands. 
It is possible that further investigations will prove that still some more 
marine birds breed in small numbers on these islands, perhaps at other seasons 
