Publ. 15. VIII. 1910. 
EUPLOEA. By H. Frijhstorfer. 
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to aruna Fruhst. (75 a) from the Aru Islands, with extended, pure white distal area on the forewing and the aruna. 
black margin broken up into separate spots and with the cell-stripes wanting on the upperside of the hind¬ 
wing, thus approaching keyensis Fruhst. from the Key Islands, which is characterized by very narrow black lceyensis. 
transverse bands, a black spot at the apex of the cell and short, awl-shaped interneural streaks. Moreover, the 
marginal band of the forewing is even more broken up than in aruna. Not rare on Great Key. 
4. Genus: Eeiploca F. 
The genus Euploea with about 140 species constitutes the most extensive Danaid-group of the eastern 
tropics. They accord well together in their similar facies and the uniform style of colouring in spite of the dif¬ 
ference in the shape of the wings and in the markings of the upperside. Ground-colour mostly brown to deep 
black, only in a few species of the Papuan region changing to violet or brown-white. Larva, as far as known, 
on Ficus and other plants with milky sap, either with 3 pairs of fleshy appendages ( Macroploea ) or 4 pairs of 
tentacles ( Crastia , Trepsichrois). Pupa thick, bell-shaped, sometimes profusely ornamented with gold and 
silver. 
One of the principal characters of the imagines consists in the concave inner margin of the forewing 
of the $3 in most species, which is usually associated with shorter or longer glossy scent-stripes. The hind¬ 
wing appears as if polished at the costal margin in the GJ (scent-patch) and mostly possesses a cavity which 
is covered with mealy scales, often modified into a thick pile ( Trepsichrois). 
The androconia are mostly club-shaped or elongate, but consist in Trepsichrois of long, thin, wavy 
threads. 
The anal pencils are different in every species and are projected by the butterflies by the pressure of 
an apparently light fluid which quickly fills in the stylus and presses out the hair-pencil. In some species this 
process is accomplished slowly; it is most rapid in Trepsichrois , which protrudes its apparatus in nervous haste 
and draws it in again, every time emitting afresh that acrid, peculiar smell, which also characterizes the ab¬ 
domen of the female. 
Some species do not emit a nauseous, but a mildly aromatic smell, such as the large, dull blue carna- 
ralzeman, which like all its nearest allies possesses at the same time the shortest pencils, which can only be 
projected with difficulty. 
Salpinx bears two rosettes of hairs placed one above the other, and it needs a fairly strong pressure 
to project the inner (upper) tuft, which moves up and down as a small yellow ball in the stylus, but cannot 
be protruded by the specimen, so far as I was able to observe in Siam. The double tuft of hairs is most devel¬ 
oped in midamus, which is even able to protrude the supposed weapon all at once. Eupl. rhadamanthus has 
the rosette light grey instead of yellow. Niceville compares the anal pencils with holy water sprinkling-brushes; 
they are always stretched out perpendicularly to the plane of the body. Judging from my preparations 
of Salpinx viola, the anal pencils are placed laterally in a throat-shaped, oval opening with somewhat SAvollen 
rim and apparently exactly in the middle of the seventh and eighth tergite, in pairs. Their radiating hairs 
look to the naked eye like black dots, but under the microscope they are long, thick tufts of hair. 
The first subcostal always arises before the end of the cell, nearly always free, only occasionally in a 
few Calliploea coincident with the costal. In all the groups subcostal 2 arises at the end of the cell, a charac¬ 
ter which in contrast to Danaida remains very constant. Tipper discocellular always present as in Hestia, al¬ 
though in some species only very short. The tertiary sexual characters on the upperside of the wings are very 
variable and are scarcely sufficient to separate the species, but have nevertheless led earlier authors to erect 
over 25 genera. 
But whilst among the Dan aids some groups can be separated structurally, in the Euploeids in spite 
of the closest investigation not the least difference can be recognized, as they remain altogether constant in 
the neuration. At the same time some of the tertiary sexual characters are useful as distinguishing marks for 
the separation of series of forms, which, however, must always be regarded as only groups, without the slight¬ 
est claim to subgeneric rank, such as must be accorded to some of the divisions of the Danaids. 
The differences in the anal pencils might offer a better basis for subdivision, but at present we are only 
able to study them conveniently at the live specimens, and hence they are still practically useless. 
In absolute contrast to the Danaids, and even to most other genera of butterflies (with the exception 
perhaps of the Brassolids), the clasping organs are of strikingly uniform structure. Form of the uncus in 16 
species and forms examined not recognizable at all. Valve broad, distally shaped like a bird’s head, the tip 
chitinized, with long shaggy hair all over, very slightly widened or narrowed according to the species, and on¬ 
ly covered with teeth in a few species ( aegyptus, leucosticlus). Saccus likewise only varying slightly in shape. 
Penis unusually long, membranous. 
Almost all the Euploeas have in common a nauseous smell, which in mulciber reaches the maximum 
of repulsiveness for the human sense of smell. Seme species smell of mignonette, others again of honey and 
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