The geographical distribution of animals, with a study of the relations ...

344 ZOOLOGICAL GEOGRAPHY. [part hi.abundant and characteristic. Out of the 41 Oriental genera 21are Malayan, and 10 of these are not found in the other subregions.In Lucanidae the Malay islands are rich, 14 out of the 16Oriental genera occurring there, and 3 being peculiar. Thereare many fine species of Odontolabris, which may be consideredthe characteristic genus of the sub-region.The Cetoniidae are well represented by 16 genera and about 120species. The genera Mycteristes, Phccdimus, Plectrone, Euremina,Rhagopteryx and Ccntrognathus are peculiar, while Agestrata,Ghalcothca, and Macronota are abundant and characteristic.The Longicorns, as in all continental forest regions near theequator, are very abundant and in endlessly varied forms. Noless than 55 genera containing about 200 species are peculiar tothis sub-region, the Cerarnbycidse being much the most numerous.Euryarthrum, Coelosterna, Ayelasta,and Astathes may be consideredas most characteristic ; but to name the curious and interestingforms would be to give a list of half the genera.Forthe relations of the Longicorns of the Indo-Malay, and those ofthe Austro-Malay region, the reader is referred to the chaptef onthe distribution of insects in the succeeding part of this work.Terrestrial Mollusca.—The Philippine islands are celebratedas being one of the richest parts of the world for land shells,about 400 species being known. The other islands of the subregionare far less rich, not more than about 100 species havingyet been described from the whole of them. Helix and Bulimusboth abound in species in the Philippines, whereas thelatter genus is very scarce in Borneo and Java.Ten genera ofHelicidse inhabit the sub-region ; Pfeifferia is found in thePhilippines and Moluccas, while the large genus Cochlostyla isalmost peculiar to the Philippines.Of the Operculata there arerepresentatives of 20 genera, of which Dermatoma and Pupinellaare peculiar, while Registoma and Callia extend to theAustralian region. Cycloplwrus, Leptopoma, and Pupina areperhaps the most characteristic genera.