Wehavenowonlytomentiontheturkey-buzzardVulturaura，andtheGallinazo。Theformerisfoundwhereverthecountryismoderatelydamp，fromCapeHorntoNorthAmerica。DifferentlyfromthePolyborusBrasiliensisandChimango，ithasfounditswaytotheFalklandIslands。Theturkey-buzzardisasolitarybird，oratmostgoesinpairs。Itmayatonceberecognisedfromalongdistance，byitslofty，soaring，andmostelegantflight。ltiswellknowntobeatruecarrion-feeder。OnthewestcoastofPatagonia，amongthethickly-woodedisletsandbrokenland，itlivesexclusivelyonwhattheseathrowsup，andonthecarcassesofdeadseals。Wherevertheseanimalsarecongregatedontherocks，therethevulturesmaybeseen。TheGallinazoCathartesatratushasadifferentrangefromthelastspecies，asitneveroccurssouthwardoflat。41degs。Azarastatesthatthereexistsatraditionthatthesebirds，atthetimeoftheconquest，werenotfoundnearMonteVideo，butthattheysubsequentlyfollowedtheinhabitantsfrommorenortherndistricts。AtthepresentdaytheyarenumerousinthevalleyoftheColorado，whichisthreehundredmilesduesouthofMonteVideo。
ItseemsprobablethatthisadditionalmigrationhashappenedsincethetimeofAzara。TheGallinazogenerallyprefersahumidclimate，orrathertheneighbourhoodoffreshwater；henceitisextremelyabundantinBrazilandLaPlata，whileitisneverfoundonthedesertandaridplainsofNorthernPatagonia，exceptingnearsomestream。ThesebirdsfrequentthewholePampastothefootoftheCordillera，butIneversaworheardofoneinChile；inPerutheyarepreservedasscavengers。Thesevulturescertainlymaybecalledgregarious，fortheyseemtohavepleasureinsociety，andarenotsolelybroughttogetherbytheattractionofacommonprey。
Onafinedayaflockmayoftenbeobservedatagreatheight，eachbirdwheelingroundandroundwithoutclosingitswings，inthemostgracefulevolutions。Thisisclearlyperformedforthemerepleasureoftheexercise，orperhapsisconnectedwiththeirmatrimonialalliances。
Ihavenowmentionedallthecarrion-feeders，exceptingthecondor，anaccountofwhichwillbemoreappropriatelyintroducedwhenwevisitacountrymorecongenialtoitshabitsthantheplainsofLaPlata。
Inabroadbandofsand-hillockswhichseparatetheLagunadelPotrerofromtheshoresofthePlata，atthedistanceofafewmilesfromMaldonado，Ifoundagroupofthosevitrified，siliceoustubes，whichareformedbylightningenteringloosesand。ThesetubesresembleineveryparticularthosefromDrigginCumberland，describedintheGeologicalTransactions。[10]Thesand-hillocksofMaldonadonotbeingprotectedbyvegetation，areconstantlychangingtheirposition。Fromthiscausethetubesprojectedabovethesurface，andnumerousfragmentslyingnear，showedthattheyhadformerlybeenburiedtoagreaterdepth。Foursetsenteredthesandperpendicularly：byworkingwithmyhandsItracedoneofthemtwofeetdeep；andsomefragmentswhichevidentlyhadbelongedtothesametube，whenaddedtotheotherpart，measuredfivefeetthreeinches。Thediameterofthewholetubewasnearlyequal，andthereforewemustsupposethatoriginallyitextendedtoamuchgreaterdepth。Thesedimensionsarehoweversmall，comparedtothoseofthetubesfromDrigg，oneofwhichwastracedtoadepthofnotlessthanthirtyfeet。