784 rROCEEDINGS OF THE NATIONAL MUSEUM. 



finally, that the remaining gecko has close relatives in New Caledonia, 

 Java, Sumatra, and Ceylon. 



This distribution does not sustain the theory of a once continuous 

 land connection between the various island groups. On the contrary, 

 the limited number and wide range of this fauna go to show that at the 

 time of immigration the Hawaiian Islands, at least, were separated, and 

 probably widely so, from whatever land masses may have connected 

 other islands at that time or earlier. 



If the meteorologic and hydrographic conditions at that time were 

 auything like what they are at present, it is not likely that these frail 

 land vertebrates were distributed over thousands of miles of ocean by 

 ordinary means. Currents and wind would have prevented their dis- 

 tribution, and such obstacles which have appeared to some authors so 

 formidable as to make them dubious concerning the western origin of 

 the Polynesian navigators themselves seem insurmountable for small 

 land vertebrates incapable of flight. 



It is a well-known fact, however, that these small lizards are easily 

 transported in vessels and among household goods over great distances, 

 and when looking for the means by which these animals may have 

 reached the Hawaiian Islands it is not possible to escape the conclu- 

 sion that they have been introduced by man's agency. From the cir- 

 cumstances that the true home of these lizards is to the south and west 

 of Hawaii; that nearly all the species were collected there as early as 

 the visit of the United States Exploring Expedition under Wilkes; and 

 that the species are more or less common on the principal islands of 

 the Hawaiian group ;^ from these circumstances it is permissible to 

 conclude that the lizards immigrated to the islands with the ancestors 

 of the Hawaiians. 



A greater antiquity in the islands can hardly be assigned to them, 

 for if their immigration was anywhere near concomitant with the first 

 appearance, for 'instance, of the ancestors of the Drepanidine birds 

 now living there, it is scarcely credible that they would not have become 

 more differentiated. The fact that specimens identical with HemiphyUo- 

 dactylus leucostictus have thus far not been found outside the Hawaiian 

 Islands does not prove anything to the contrary, partly because it is 

 possible that they may be found iu some of the as yet but little explored 

 archipelagoes to the west and south, and partly because the differences 

 which distinguish this gecko from its nearest allies are so slight that it 

 is conceivable that they may have been evolved since the advent of 

 man in the islands. 



At the present stage of our knowledge the distribution of these ani- 

 mals throws very little light ui)on the question by which route they and 

 man — if it be true that they accompanied him — reached the archipelago. 



'Thus far, specimens have only been collected in Hawaii, Molokai, Oahu, and 

 Kauai; but there is no reason to believe that they are not also to be found on the 

 intervening islands. 



