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Show 1889.] RELATIONSHIPS OF PALAWAN ISLAND. 223 up of soft decomposable rocks which are readily degraded by denudational agencies; and no one who has watched the larger rivers of the island incessantly discharging their yellow mud-laden floods seawards will be disposed to doubt that they must have done much towards shallowing of the Macassar strait. But this agency cannot be called in to explain the existence of the shallow bank connecting Borneo with the Palawan group ; for all the rivers discharging on to this bank are of quite insignificant size, and therefore it may be regarded as having formed for some time past a permanent feature in the local geography, whereas the Macassar bank is a recent feature still in process of construction. The Palawan bank may have been, and almost certainly has been, submerged far below its present level; but the probability is equal that it has also been elevated into dry land and a temporary junction formed-perhaps more than once- with Borneo. Proceeding now to inquire what light is thrown upon the connexion of Palawan with Borneo on the one side or the Philippines on the other by the characteristics of the fauna of the Palawan group, we are met with the difficulty that the only classes of animals from these islands which are fairly well known are the mammals and the birds. On the other hand evidence derived from the distributional relationships of these two classes has admittedly a high value for the purpose in view. The mammals which are known to exist in the Palawan group are the following :- 1. Macacus cynomolyus ... Common to Philippines and Indo-Malayaproper. 2. Felis minuta Indo-Malaya Proper and I. of Negros. 3. Paradoxurus philippensis Common to Philippines and N. Borneo. 4. Arctictis binturong Nepal to Borneo. 5. Herpestes brachyurus ... Malay Peninsnla and Borneo. 6. Mydaus, sp. (P)1 Sumatra, Java, and N. and E. Borneo. 7. Lutra, sp Genus abundant in N. Borneo. 8. Tragulus javanicus Indo-Malaya Proper and I. of Balabac. 9. Sus, sp Genus common to Philippines and Borneo. 10. Sciuropterus alboniger ... Nepal to Cambodja. 11. Sciurus steerii Allied to S. ferrugineiis of Assam, Burmah, and Siam. 12. Mus, sp Genus common to Philippines and Borneo. 13. Hystrix pumila Genus abundant in N. Borneo. 14. Tupaia ja vanica Indo-Mal aya Proper. Abundant in Borneo. 15. --ferruginea Indo-Malaya Proper. Abundant in Borneo. If5. Pteropus hypomelanus ... Philippines, Borneo, Celebes, and N. Guinea. 17. Kerivoula hardwickii ... India, Java, Borneo. 18. Manis, sp Genus very abundant in N. Borneo. The above enumeration shows that the Palawan group possesses a mammalian fauna (exclusive of Bats) comparable in variety of species and genera with that of the entire Philippine Archipelago. Of the species composing this fauila only one, the Paradoxure, namely, can be regarded as a distinctively Philippine species, and even that one occurs also in Northern Borneo. The remaining mammals, after putting on one side those which are common to the Philippines and 1 This animal has never been actually obtained, I believe, by any collector, but it has frequently been described to me by Europeans as well as by natives. |