304 Letters, Extracts, Notices, §c. 



Eighty species of birds are assigned to the Galapagan 

 Avifauna in this memoir, besides some 40 subspecies. It will 

 be observed that the original idea of the term " subspecies " 

 being restricted to cases in which intermediate forms occur 

 lias here been quite abandoned. There are, of course, no 

 intermediate forms between species confined to different 

 islands, but they are none the less treated as " subspecies." 



The field-notes are of great interest, especially those 

 relating to the Geospizine Finches, which appear to have 

 been very carefully studied. They are all placed by the 

 authors in one genus (Geospiza) ,with 18 species and numerous 

 subspecies. Certhidea, referred to the Mniotiltidie, has 2 

 species, which are divided into 8 subspecies. 



It must not be supposed, however, from what has been 

 said that we do not approve of this piece of work. On the 

 contrary, it is a valuable contribution to a most engaging 

 subject — that of the origin of insular Avifaunas. Next to 

 the Hawaiian Archipelago, the Galapagan group perhaps 

 presents a more favourable opportunity for the discussion 

 of this most interesting question than any other part of the 

 earth's surface. We are therefore grateful to Messrs. Snod- 

 grass and Heller for the pains which they have taken in 

 working out this important collection. 



Gl. Stejneger on Oreomyza. 



[A new Name for the Hawaiian Bird-genus Oreomyza. By Lconhard 

 Stejneger. Pr. Biol. Soc. Washington, xvi. p. 11 (1903).] 



Oreomystis is proposed, Oreomyza being already occupied 

 in entomology. 



XXIII. — Letters, Extracts. Notices, and Obituary. 



We have received the following letters addressed to "The 

 Editors of < The Ibis ' " :— 



Sirs, — On a recent passage from New York to England I 

 was struck by observing Snow-Buntings (Plectrqpkanes ni- 

 valis) on migration in mid-Atlantic. I was previously under 

 the impression that this species migrated practically North 

 and South. That numbers of them apparently cross the 



