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CHAP. XV.] THE NEARCTIC REGION. 123
forms. A considerable number oOTeotropical types enter the
southern States ;
but there are hardfrany peculiar genera, except
one of the Lycsenidae and perhaps a few among the Hesperidse.
The most conspicuous feature of the region is its fine group of
Papilios, belonging to types (P. turnus and P. troilus) wliich are
cliaracteristically Nearctic. It is also as rich as the Palsearctic
region in some genera which we are accustomed to consider
as pre-eminently European ; such as Argynnis, Melitcea, Gmpta,
Chionahas, and a few others. Still, we must acknowledge, that
if we formed our conclusions from the butterflies alone, we could
hardly separate the Nearctic from the Paleearctic region. This
identity probably dates from the Miocene period ;
for when our
existing arctic regions supported a luxuriant vegetation, butterflies
would have been plentiful ; and as the cold came on, these would
move southwards both in America and Europe, and, owing to the
long continuance of the generic types of insects, would remain
little modified till now.
CoU(yptera.—Only a few indications can be given of the
peculiarities of the Nearctic coleoptera. In Cicindelidte the
region possesses, besides the cosmopolite Cicindela, four other
genera, two of which
—
Amhlychile and Omus—are peculiar to
the West Coast and the Eocky Mountains. Of Carabidee it
possesses Dicmlus, Pasimachus, Eurytrichus, Sphceroderus, Pina-
codera, and a number of smaller genera, altogether peculiar to it
Helluomorpha, Galerita, Callida, and Tetragonoderus, in common
with South America; and a large number of characteristic
European forms. »
The Lucanidae are all of European types. The region is poor
in Cetoniidae, but has representatives of the South American
Euphoria, as well as of four European genera. Of Buprestidse
it has the South American Adenodes ; a single species of the
Ethiopian and Eastern Belionota, in California ; and about a
dozen other genera of European and wide distribution.
Among Longicorns it possesses fifty-nine peculiar genera,
representatives of five Neotropical, and thirteen Palaearctic genera;
as well as many of wider distribution. Prionus is the chief
representative of the Prionidae; Leptura and Crossidius of the
;