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CHAP. XXI.] INSECTS. 405
to Australia and South America. The Nearctic and Palsearctic
regions have 3 genera in common, which are found in no other
part of the world.
Among the special features of interest connected with the
distribution of this family, we must first notice the exceptional
richness of Madagascar, which alone possesses 21 peculiar
aenera. South Africa is also very rich, having 8 peculiar
o-enera. Stethodesma is very peculiar, being divided between
South America and Mexico on the one hand, and West and
South Africa on the other. Stalagmosoma is a desert genus,
ranging from Persia to Dongola. No genus is cosmopolitan, or
even makes any approach to being so, except Valgus, which
occurs in all the regions except the Neotropical ; and even the
family seems to be not universally distributed, since no species
are recorded either from New Zealand, the Pacific Islands, or
the Antilles.
The facts here brought forward, lead us to the conclusion that
the Cetoniidffi are an Old-World tropical family, which had
been well developed in Africa and Asia before it spread to
Australia and America; and that it is only capable of being
freely dispersed in the warmer regions of the earth. This view
will explain the absence of affinity between the Australian and
Neotropical regions, the only closer connection between which,
has almost certainly occurred in the colder portions of the Tem-
perate zone.
BUPEESTID^. (109 Genera, 2,686 Species,)
The next family suited to our purpose is that of the Bupres-
tid£e, consisting as it does of many large and some gigantic
species, generally adorned with brilliant metallic colours, and
attracting attention in all warm countries. Although these in-
sects attain their full development of size and beauty only in
the Tropics, they are not much less abundant in the warmer
parts of the Temperate zone. Iii the Catalogue of the Coleop-
tera of Europe and the Mediterranean Basin, by M. de Marseul
(1863), we find 317 species of Buprestidse enumerated, although