no. I7.:i. FORMOSA V i: I TR Will I \ S I WD REPTILEU UTI-JJ \ EGER. 93 



the more eastern provinces of thai empire, as it is quite likely that 

 those gaps may be filled when the mountain districts of southeastern 

 China shall become better known, but rather to emphasize t he si rong 



connection between the Formosan species and those inhabiting the 

 eastern Himalayas and the high land to the east. 



This relationship is not only manifested by the peculiar species, 

 but by the rest of the reptilian fauna as well. Leaving oul the geckos 

 and skinks, the geographical distribution of which is subject to so 

 many accidental circumstances, we have 35 species of land reptiles 

 left, which also occur outside of Formosa. Of these 3 are of very 

 wide distribution, extending into the Malayan Archipelago, but not 

 occurring in the Himalayas or the high land to the east. These are, 

 therefore, species of decidedly southern affinities. Seven species 

 which occur in southern China, some of them extending southward 

 into Indo-China and Siam, may be included in this category. Ten 

 species are of more or less general distribution in eastern China. 

 Finally, 15 species, one of which is doubtful, occur in the eastern 

 Himalayas or the high land to the east or both. 



On the other hand, none of the Formosan batrachians occurring 

 outside the island are found in the Himalayas or the high land to the 

 east. Of the 10 species 4 are wide-ranging and southern, 2 likewise 

 southern but of more restricted distribution, 1 is strictly eastern 

 Chinese, while 3 are also found in the Riu Kin Islands, 1 of undoubted 

 southern affinity, the other 2 probably likewise. 



It will thus be seen that all the batrachians which have Himalo- 

 Chinese affinities have differentiated into more or less distinct species, 

 while those of southern affinities have remained nearly unchanged. 

 It is also evident that the reptiles of southern admit ies have remained 

 practically unaltered in the island and that the specific differentia- 

 tion almost exclusively took place among the Himalo-Chinese species; 

 but the amount of differentiation in the reptiles was not nearly as 

 large, for while it affected all the batrachians, it affected only 44 per 

 cent of the reptiles. Whatever may be the reason for the greater 

 amount of batrachian differentiation, the fact that practically no 

 southern forms have undergone special ion in the island seems to 

 indicate most plainly that the Himalo-Chinese component of the 

 herpetological fauna of Formosa has lived much longer in the island 

 than the more southern element, which musl be ;i later arrival. 



In this review of the relationship of the Formosan herpetological 

 fauna the most striking fact, next to the prevalence of the Himalo- 

 Chinese element, is the total absence of any indication of affinity to 

 the fauna of the Philippine Islands directly to the south. A number 

 of wide-ranging species of southern origin occur in both faunas, bul 

 as these also occur in southern China, on the mainland opposite For- 



