THE ANIMAL LIFE OF TIIH GROFP. 335 



genus are rapidly dying out, apparently of their own accord, or at least from 

 other unassignable causes. The Oaliu species ^i has long been extinct. 



Hawaiian Duck and Goose. 



The Hawaiian duck,'- the gallenuU' and llic cool are diininishint: in num- 

 bers on all the islands where the mongoose is i'ound; while the put'iin. llie 

 petrel and the native goose ^^ are all sub.iect to its toll. 



All of these birds are becoming extinct from known causes, ]»nt thci-c are 

 species which have died out for no assignable reason. The splendid Chaioptila 

 o))gi(s:fiph(}}ia of Hawaii is a case in point. Though it was rare when first dis- 

 covered by naturalists, it has not lieen seen in the forests iVom that da\- to the 

 present. 



Likewise, there seems to be no adequate explanation for the extinction of 

 at least five of the six species that are now known from only a few luuseuni 

 specimens collected by early naturalists, as only one of the extinct species, 

 namely, the Oahu mamo, was ever killed by the natives for their feathers. 

 Although numerous theories have been advanced, the cause of their extermination 

 will doubtless ever remain one of nature's own secrets. 



In considering the future of the Hawaiian birds, especially those that 

 have been rare or very limited in their distril)ution, we must remember that 

 the forest areas are diminishing owing to the devastation of animals, the ax 

 and the settler, and that in consequence the birds are constantly being brought 

 into sharper competition among themselves and into a struggle with a differcMit 

 if not a new environment. 



Already several species that a decade ago were regarded as fairly connnon 

 in certain localites have disappeared from them entirely. Avhile others are only 

 found after long and diligent search. 



Hawaiian Crow. 



An interesting phase of Hawaiian bird life is shown I)\ the nati\f Ha- 

 waiian crow.i^ It occurs on a certain portion of one island only, and there 

 over an area from which it never seems to attempt to pass. IIa\iiig originally- 

 gained a foothold in the Kona and Kau districts of Hawaii, the bird seems to 

 be unwilling to extend its range to the windward forests that ad.join is liab- 

 itat, even though they are known to abound in suitabh^ food. 



The VIridonia ^'> is a handsome olive-^i-een bird which fni'iiishes a still 

 more remarkable instance of a restrictetl habitat. Tliis, one of the rarest of 

 Hawaiian birds, is only found on Hawaii, and there it is confined to an area 

 of a few square miles and is absolntely nnioiown ontside this little valley 

 region, where it was so rare as to be unknown to tlie native inhabitants. 



The Black ^Iamo. 

 The hoi or Idack mamo "' is confined to the Island of Molokai. There it 



11 ilfo/io aincnUs. ^' Ai^as iri/rilliann. ^'^ Kesorlit-n sinidrirfiinix. ^* Cnrius hawaiieiisis. 



1^ V. sagittirostris. i" DreDanorliaiipns funerea. 



