AUSTRO-MALATSIAN- TRANSITIQIT EEGIOX. 107 



more distinctly of a southern than of a northern facies. Of some 

 filty-five or more species of lacertilians, very nearly three-fourths of 

 the number are iguanas (Iguanidae), and four are geckoes. Fully 

 one-half of the total number of genera represented are not found in 

 other portions of the North American continent. The serpent- 

 fauna comprises about twenty-two genera, one-half of which are 

 peculiar. Eleven of the thirteen species of North American rattle- 

 snake are found here ; the otherwise common coluber is wanting. 

 Among the tailless amphibians, the Bufonidffl (Bufo) have their 

 headquarters here, more than one-half of all the North American 

 species being represented. The tree-frogs (HylidseJ, and frogs 

 proper (Ranidse), are, on the other hand, both very deficient. The 

 tailed amphibians, of which there are upwards of fifty species in 

 the region to the north, are almost completely wanting.-* 



THK AUSTBO-MALAYSIAN TBANSITION EEGION. 



This region, which is situated intermediately between the Ori- 

 ental and Australian realms, naturally partakes of an intermediate 

 position also in respect of its fauna. While the animal types bor- 

 rowed from the adjoining regions preponderate to a very marked 

 extent, the number of specific forms that are absolutely peculiar, 

 especially among birds, is very remarkable. According to Mr. 

 Wallace nearly three-fourths of some two hundred species of land- 

 birds inhabiting the Moluccas are peculiar to those islands, and very 

 nearly one-half of a hundred and fifty or more species found on the 

 island of Celebes are absolutely confined to it. Yet, of the one 

 hundred and twenty genera here represented (Celebes), only nine 

 are peculiar. With few exceptions, all the families of birds that 

 are represented in either the Australian or the Oriental region are 

 also represented here. As belonging to the former, the birds-of- 

 paradise have but a single species, the standard-wing (Semioptera 

 Wallacei), found in the islands of Gilolo and Batchian ; the honey- 

 suckers appear to be almost entirely absent from Celebes, although 

 they are to be found in several of the other islands. The Oriental 

 babbling-thrushes (Timalidse) and bulbuls (Pycnonotid») barely en- 

 ter, while the hill-tits (Leiotrichidee) are completely wanting. It is 

 not a little remarkable that the creepers (Certhiadas), stone-hatches 

 (Sittidse), and tits (Paridse), which have their representatives in 



