The geographical distribution of animals, with a study of the relations ...

;chap, xii.] THE ORIENTAL REGION. 355would alone enable us to trace. Should we ever arrive at afair knowledge of the physical changes that have resulted inthe present condition, we shall almost certainly find that manyof the differences and anomalies of their existing fauna andflora will be accounted for.In Birds we hardly find anything to differentiate Borneo andSumatra in any clear manner.Pityriasis and Carpococcyx, oncethought peculiar to the former, are now found also in the latterand we have not a single genus left to characterize Borneo exceptScluvaneria a peculiar fly-catcher, and Indicator, an African andIndian group not known to occur elsewhere in the Malaysub-region.Sumatra as yet alone possesses Psil&pogon, a remarkableform of barbet, but we may well expect that itwill be soonfound in the interior of Borneo or Malacca ; it also has Berenicornis,an African form of hornbill. The Malay Peninsulaappears to have no genus peculiar to it, but it possessessome Chinese and Indian forms which do not pass into theislands.As to the species, our knowledge of them is at presentvery imperfect. The Malay Peninsula is perhaps the bestknown, but it is probable that both Sumatra and Borneo arequite as rich in species. With the exception of the generanoted above, and two or three others as yet found in two islandsonly, the three districts we arenow considering may be said tohave an almost identical bird-fauna, consisting largely of thesame species and almost wholly of these together withcloselyallied species of the same genera. There are no well-markedgroups which especially characterise one of these islands ratherthan the other, so that even the amount of speciality whichBorneo undoubtedly exhibits as regards mammalia, is onlyfaintly shown by its birds. The Pittidae may perhaps be namedas the most characteristic Bornean group, that island possessingmost beautiful birds of an unusually beautiful family.six species, three of which are peculiar to it and are among theYet Sumatrapossesses two peculiar, and hardly less remarkable species.In other classes of vertebrates, in insects, and in land-shells,our knowledge is far too imperfect touseful comparison between the faunas.allow of our making any