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496 GEOGRAPHICAL ZOOLOGY. [part iv.
the district in question only forms a part of tlie Palsearctic
region, which would thus seem to possess its full proportion of
the species of this family. Confining ourselves to the generic
forms, we find far less difference than usual between the
numbers possessed by the tropical and the temperate regions
the richest being the Australian, with 47 genera, 20 of which
are peculiar ; and the poorest the Nearctic, with 24 genera, of
which 7 are peculiar. The Oriental has 41 genera, 14 of which
are peculiar ; the Neotropical 39, of which the large proportion
of 18 are peculiar; the Ethiopian 27, of which 6 are peculiar;
and the Palsearctic also 27, but with 9 peculiar.
A most interesting feature in the distribution of this family,
is the strong affinity shown to exist between the Australian
and Neotropical regions, which have 4 genera common to both
and found nowhere else ; but besides this, the extensive and
highly characteristic Australian genus, Stigmodera, is closely
related to a number of peculiar South American genera, such as
Conognatha, Hyperantha, Dadylozodes,—the last altogether con-
fined to Chili and Temperate South America. Here we have
a striking contrast to the Cetoniidse, and we can hardly help
concluding, that, as the latter is typically a tropical group, so
the present family, although now so largely tropical, had an
early and perhaps original development in the temperate regions
of Australia, spreading thence to Temperate South America as
well as to the tropical regions of Asia and Africa. The
Australian and Oriental regions have 4 genera exclusively in
common, but they also each possess a number of peculiar or
characteristic genera, such as the Indo-Malayan Catoxantha
(which has only a single species in the Moluccas) and nine others
of less importance ; and the exclusively Austro-Malayan genus,
Samhus, with five smaller groups, and Cyphogastra, with only 2
Indo-Malay species. The Oriental and Ethiopian regions are very
distinct, only possessing the single genus, Sternoccra, exclusively
in common. The Nearctic and Palasarctic are also distinct, only
one genus, Dicerca, being confined to America (North and South)
and Europe, a fact which again points to a southern origin for
this family, and its comparatively recent extension into the
;