CHAP. XU.] 
TIIE ORIENTAL REGION. 
341 
Kalophrymts, Ansonia, and Fseudobufo . are peculiar : while the 
Oriental Megalophrys, Imlus, Rhacophorus, and Hylorana are 
abundant and characteristic. 
Fishes . — The fresli-water fishes of the Malay archipelago 
have been so well collected and examined by the Dutch 
naturalists, that they offer valuable indications of zoo-geo- 
graphical affinity ; and they particularly well exhibit the 
sharply defined limits of the region, a large number of Oriental 
and even Ethiopian genera extending eastward as far as Java 
and Borneo, but very rarely indeed sending a single species 
further east, to Celebes or the Moluccas. Thirteen families of 
fresh-water fishes are found in the Indo-Malay sub-region. Of 
these the Scienidse and Symbranchid© have mostly a wide 
range in the tropics. Ophioceplialid© are exclusively Oriental, 
reaching Borneo and the Philippine islands. The Mastacem- 
belidse are also Oriental, but one species is found as far as Ceram. 
Of the Nandid©, 3 genera range over the whole region. The 
Labyrinthici extend from Africa through the Oriental region to 
Amboyna, The single species constituting the family Lucio- 
cephalid© is confined to Borneo and the small islands of Biliton 
and Banca. Of the extensive family Siluridaa 17 genera are 
Oriental and Malayan, and 11 are Malayan exclusively; and 
not one of these appears to pass beyond the limits of the sub- 
region. The Cyprinid© offer an equally striking example, 23 
genera ranging eastward to Java and Borneo and not one 
beyond; 14 of these being exclusively Malayan. It must be 
remembered that this is not from any want of knowledge of the 
countries farther east, as extensive collections have also been 
made in Celebes, the Moluccas, and Timor; so that the facts of 
distribution of fresh-water fishes come, most unexpectedly, to 
fortify that division of the archipelago into two primary 
regions, which was founded on a consideration of mammalia 
and birds only. 
Insects . — Few countries in the world can present a richer and 
more varied series of insects than the Indo-Malay islands, and 
we can only here notice a few 7 of their more striking peculiarities 
and more salient features. 
