BATKACHIAXS. 317 



to be of the type in which the metamorphoses are hurried through 

 within the egg. These horned frogs are very numerous in the 

 islands of Bougainville Straits, and so closely do they imitate their 

 surroundings, both in colour and pattern, that on one occasion I 

 captured a specimen by accidentally placing my hand upon it when 

 clasping a tree. 



It is particularly important to notice not only that the Batra- 

 chians of the Solomon Islands, as far as we at present know, do not 

 occur elsewhere, but also that in this region a distinct family has 

 been produced. Tiiese facts support the conclusions deducible from 

 the geological evidence that these islands are of considerable geo- 

 logical age {vide pagex. ). The insular and isolated conditions have 

 been preserved during a period sufficiently extended for the develop- 

 ment of a peculiar Batrachian fauna. 



The modes of dispersal of frogs and toads, and, in truth, of the 

 whole Batrachian class, are matters of which we are to a great extent 

 ignorant. Frogs are usually stated to be absent from oceanic islands, 

 a peculiarity of distribution which apparently accords with the cir- 

 cumstance that neither they nor tlieir spawn can sustain submei'sion 

 in sea-water. The occurrence, however, of three species of Cornujer 

 in the Caroline and Fiji Islands, and of a species of Bato in the 

 Sandwich Islands,^ affects the general application of this conclusion. 

 It may be suggested that .these exceptions are due to human agency; 

 but if so, it is difficult to understand why they have not been found 

 in such a well explored island as New Caledonia.^ 



In concluding this chapter I will refer to the circumstance that 

 my collections of the Reptiles and Batrachians of this large group 

 have only in a manner broken ground in a region which promises 

 the richest results to the collector. It cannot bo doubted that in 

 the elevated interiors of the large islands, such as those of Bougain- 

 ville and Guadalcanar, there will be found a peculiar Reptilian and 

 Batrachian fauna, the study of which will be of the highest import- 

 ance for the furtherance of our knowledge of these geologically 

 ancient classes of animals. I believe I am correct in stating; that it 

 was on account of the highly interesting Batrachian collections I 

 sent to the British Museum, .that I received a grant for further ex- 

 ploration from the Royal Society, which, however, I was unfortu- 



1 Boulenger's " Catalogue of the Batrachia Gradientia," &c., 2nd edit., 1882. 

 - Perhaps the peculiar geograi^hical distribution of the Batrachia may throw light on thi» 

 subject. Ibid. 



