92 BARBOUR — SOLOMON ISLAND REPTILES ['''v^l^V^lF* 



The fauna of the Solomons, so far as concerns the reptiles and 

 I amphibians, is obviously Papuan and not AustraUan in its 

 j origin. The fauna of the group also is more homogeneous than 

 at first appeared, when Boulenger noted that Faro was more 

 Papuan than San Cristobal. This homogeneity is most signifi- 

 cant, for the species which occur widely in the Solomons, in gen- 

 eral are absent from New Britain and New Ireland, and this fact 

 indicates a long period of isolation during which the islands were 

 not broken up into small land masses as they are at present. The ■ 

 phylogenetic development of Ceraiobatrachus and Batrachylodes 

 must perforce have been a slow process. The latter was supposed 

 to be confined to Faro, but Dr. Mann found it upon New Georgia, 

 hence it probably occurs as widely spread as Ceratohatrachus 

 itself, which is better known since it is far more conspicuous. 

 Dr. Mann's large series of several of the amphibians reveal 

 hitherto unsuspected variability, and several species in the past 

 considered to be distinct are forced into the synonymy. This 

 affects the number of species of Rana, Hyla and Cornufer which 

 have been recorded. But after these reductions have been made, 

 and the new locahty records added, the final facies of the fauna 

 remains essentially unchanged. It still appears an ancient, 

 somewhat depauperate, continental, and not an oceanic, fauna 

 which probably has spread under rather adverse conditions. The 

 amphibians reaching the group are those which could disperse 

 themselves and reproduce in areas where standing water in the 

 shape of ponds or permanent pools is practically non-existent, 

 and where heavy rainfall and steep hills combine to form tor- 

 rents which would carry off larvae rather than permit their 

 leisurely development. Thus those forms have persisted, which 

 have skipped a free-swimming larval stage. Van Kampen has 

 well expressed these ideas. (Bijblad. Nat. tijd Ned. Indie, 3, 4, 

 1909, pp. 1-24. Translated by T. Barbour, Amer. Nat., 45, 

 1911, p. 537-560). A general discussion of the relation of the 

 fauna of the Solomon Islands with that of the neighboring 

 regions may be found in my ' Contribution to the Zoogeography 

 of the East Indian Islands.' (Mem. M.C.Z., 44, 1912, p. 59-62.) 



