622 Recently published Ornitholoyical Works. [Ibis, 



is, in regard to the treatment of the case of the Brent Geese 

 in the two recently published Lists of British Birds. It is 

 often difficult to settle whether a plumage-variation indicates 

 dimorphism or a distinct race. This can only be settled by 

 observation at the breeding-grounds. If the two forms 

 breed together we may take it that there is only one race 

 or species-form. If the breeding-grounds are entirely 

 distinct we can conclude that there are two separate sub- 

 species, though closely allied subspecies are often found 

 mingled in the same flocks in. winter. 



If the dark- and light-breasted Brents breed together on 

 Kolguev, it seems probable that there is only one species 

 which occurs in two dimorphic forms, just as is the case 

 with the Arctic Skua. 



Dabbene on Argentine Birds. 



[Especies y subespecies aparamente nuevas de Geositta y Cinclodes 

 de la Republica Argentina y del sur de Cliilo por Roberto Dabbene. 

 Phyeis, Buenos Aires, iii. 1917, pp. 52-59.] 



In this short paper Senor Dabbene describes Geositta 

 pnnensis sp. n., from the provinces of Jujuy and Salta, 

 G. rujipennis burmeisteri subsp. n., from the mountain 

 regions on the boundary of the Argentine and Bolivia, 

 Cinclodes oustaleti hornensis and C. antarcticus maculirostris 

 subspp. n., from Hermit Island at the southern extremity 

 of America near Cape Horn. 



He promises in the near future to provide us with a 

 complete account of the forms of the two genera in question, 

 based on the large collections from the Argentine and 

 elsewhere preserved in the Museum at Buenos Aires. 



Dixon on the Baird Sandpiper. 



[The Home-life of tbe Baird Sandpiper. By Joseph Dixon. Condor, 

 xix. 1917, pp. 77-84 ; map and 5 photos.] 



Baird's Sandpiper [Pisobia or Tringa bairdi) is an inter- 

 esting little Wader which has been reported four times in 

 the British Isles and has been erroneously, as it seems (see 



