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XXXII. Contributions to an Insect Fauna of the Amazon Valley. Lepidoptera 
Heliconid^:. By Henry Walter Bates, Esq. (Communicated by the Secretary.) * 
Read November 21st, 1861. 
" Die wissenschaftliche Untersuchung der Natur strebt in den Einzelheiten das Allgemeine zu erkennen, urn endlich 
dem Grunde aller Dinge naher zu kommen. Fur diese Art Untersuchungen, die immer das Ziel der Naturforschung 
sein sollte, bietet wohl keine Thierclasse so reichen StofF als die Insecten." — Karl Ernst von Baer, Address on the 
Opening of the Russian Entomological Society, St. Petersburg, May 1860. 
THE family Heliconidce was established by Mr. E. Doubleday in 1847, in Doubleday 
and Hewitson's 'Genera of Diurnal Lepidoptera.' It was founded on a number of 
Butterflies, remarkable for the elongated shape of their wings, and peculiar (with the 
exception of one genus, Hamadryas, which the author placed provisionally in the family, 
op. cit. p. 98) to the intertropical and subtropical zones of America. Many of them had 
been described by the older authors under Heliconia, Mechanitis, and several other 
ill-defined genera. They had been previously (in 1836) united in a tribe, Helicon ides, 
by Dr. Boisduval in his ' Species General des Lepidopteres ;' but this comprehended also 
the group Acrceidce, which Doubleday excluded from the family. Linnseus treated them 
as a section of the genus Papilio, under the name of Heliconii. The nearest allies of the 
Heliconidce are the Acrceidce just mentioned and the Danaidce : all are distinguished 
from the true Nymphalidw by the discoidal cell of the hind wings being always closed 
by perfect tubular nervules. Mr. Doubleday, placing more reliance on the shape of the 
antenna? and the abdominal border of the hind wings than on the far more important 
character above named, was led to exclude the genus Eueides from the family : this 
rendered the definition of the two groups very difficult, if not impossible, Eueides having 
the wing-cells closed in the same way as the Heliconida. Excepting that I re-admit 
Eueides, and exclude Hamadryas, which does not enter into the series of the American 
Heliconidce, the family will be treated of in the present memoir as defined m the work 
above quoted. 
The position of the Belkmidw in the order lepidoptera may be understood when I 
state that in a natural system the group would stand at the head of the whole series of 
families of which the order is composed. At least, this should be its place according to 
the view now taken of the order by many systematists, who arrange the famines of 
Bhopalocem, or Butterflies, according to their degree of dissimilarity to the Seterocera, 
or Moths-in other words, according as their structure shows a lower or a higher stage 
ascendins; scale of 
p or> a s the lower families of Moths are allied 
other ordersTinTectVthelurthera .group recedes from them in structure, the higher is 
the grade of perfection of the Lepidopterous type which it exhibits. The families show 
their degree of affinity to Moths by many characters, the principal of which is the 
• The materials on which this memoir is founded were eolleeted by the author during eleven years' research on the 
banks of the Amazons 
VOL. XXIII. 
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