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

:284 ZOOLOGICAL GEOGRAPHY. [part hi.African genera ; but Coptops is Oriental, and the OrientalPraonetha occurs in the Comoro Islands. Among the peculiargenera several have African affinities, but Tropidema belongs toa group which is Oriental and Australian ;Oopsis is found alsoin the Pacific Islands ;allied to Malayan and American genera.Mythergates, Sulemus, and Coedomcea, areGeneral Remarks on the Insect-fauna of Madagascar.—Takingthe insects as a whole, we find the remarkable result that theiraffinities are largely Oriental, Australian, and South Americanwhile the African element is represented chiefly by specialSouth African or West African forms, rather than by such asare widely spread over the Ethiopian region. 1 In somefamilies—as Cetoniidse and Lamiidre—the African elementappears to preponderate ; in others—as Cicindelidce—the SouthAmerican affinity seems strongest ; in Carabidse, perhaps theOriental ; while in Buprestida3 and Cerambycidae the Africanand foreign elements seem nearly balanced. We must not imputetoo much importance to these foreign alliances amonginsects, because we find examples of them inevery country onthe globe. The reason they are so much more pronounced inMadagascar may be,that during long periods of time this islandhas served as a refuge for groups that have been dying out onthe great continents ; and that, owing to the numerous deficienciesof a somewhat similar kind in the seriesof vertebratain Australia and South America, the same groups have oftenbeen able to maintain themselves in all these countries as wellas in Madagascar.It must be remembered too, that these peculiaritiesin the Malagasy and Mascarene insect-fauna are but exaggerationsof a like phenomenon on the mainland. Africa alsohas numerous affinities with South America, with the Malaycountries, and with Australia ;but they do not bear anything likeso large a proportion to the whole fauna, and do not, therefore,attract so much attention. The special conditions of existenceand the long-continued isolation of Madagascar, will account formuch of this difference ;and it will evidently not be necessary1There are also some special resemblances between the plants of Madagascarand South Africa, according to Dr. Kirk.