Amongst the Insectivora very peculiar forms are found, such as Gymnura and Tupaia.
The Insectivora are certainly the lowest group of existing placental mammals, and exhibit many signs of affinity with marsupials; they may even be a more generalized group than the latter.
From the Insectivora the bats, or Chiroptera, are evidently a specialized lateral offshoot; while the Dermoptera ma y be another branch from the same stock.
Molar teeth of the simple tritubercular type persist in the golden moles (Chrysochloris) among the Insectivora and also in the marsupial mole (Notoryctes) among the marsupials.
The same conclusion is indicated by the absence from the Moluccas and Celebes of various other Mammals, Quadrumana, Carnivora, Insectivora and Ruminants, which abound in the western part of the Archipelago.
JUMPING-SHREW, a popular name for any of the terrestrial insectivora of the African family Macroscelididae, of which there are a number of species ranging over the African continent, representing the tree-shrews of Asia.
Other peculiar animals are twenty-three species of the Centetidae, a family of the Insectivora almost confined to Madagascar; while of the Carnivora there are several small creatures belonging to the civets (Viverridae).
Of the Insectivora numerous forms of moles, shrews and hedgehogs prevail.
A lemur and one of the curious hedgehog-like Insectivora of Madagascar (Centetes ecaudatus) have probably both been brought from the larger island.
The Insectivora (except a few shrews which have entered from the north) are absent from South America, and appear to have been mainly an Old World group, the only forms which have entered North America being the shrew-mice (Soricidae) and moles (Talpidae).