AGERONIIDI; ECTIMA. By Dr. A. Srrrz. 535 
to the lateral line, darker. On the second thoracal ring there are 2 long branched spines, on the one beyond, as 
well as on the third and the last abdominal rings there are spiny knobs: on Populus. Pupae brownish (in the 
beginning greenish), the wing-partitions darker, the abdominal part lighter; the dorsal appendage yellowish- 
brown. The butterfly is distributed especially in the western part of North America, more common in the 
mountains, especially in the Rocky Mountains, its range extending in the United States from Montana and 
Nebrasca to the western coast. 
L. arthemis. Similar to the preceding, though quite different on the under surface being dark brown 
traversed by the white band, with orange dots in the wing-cell and before the margin. The ordinary form 
arthemis Drury (= lamina /’.) (109 e) has very broad white bands, resembling thus somewhat on the upper arthemis. 
surface weidemeyer? as well as certain forms of the Old World. — In the form proserpina Hdw. (109 e), however, proserpina. 
the white bands may be obliterated, in rare cases even disappear altogether, whereby great likeness with astyanax 
is created, especially when there is also an increase of the blue colour on the hindwings. In that case, however, 
the orange-red submarginal spots on the under surface of the hindwings mostly shine through to the upper 
surface, in some cases even creating a simultaneous increase of the yellowish-red colour, which has led to the 
denomination of rufescens Chil. proserpina is also mostly considerably smaller than astyanax. — Egg green, r1fescens 
larva, when grown up, dark brown (rarely olive-green), with a white dorsal saddle on the fifth to eighth 
abdominal ring. The thickened second thoracal ring bears no branched spines like the preceding forms, but 
two truncated cones being spinose above, the second abdominal ring is tuberous as well as the last but one. 
Tt lives on Crataegus, Salix and probably also on other plants. The butterfly flies on roads near wet places, is 
often common in Southern Canada and the Northern United States to the south as far as Pennsylvania, but 
is absent in the whole west. According to HOLLAND it reaches altitudes of 2500 m. 
K. Group Ageroniidi. 
This is one of the most peculiar groups of day-butterflies confined exclusively to America. The main 
group Ageronia (Peridromia) is supplied with an organ of sounds, a peculiar kind of rattling or clattering, which 
belongs to the most energetic sounds created by insects. A rattling Ageronia flying over the road even attracts 
the attention of the passers-by and in the silent woods I was able to hear the noise from a distance of 40 paces 
without listening intently. The butterflies, therefore, have the popular name of ,,rattlets“ or ,,clatters*’ (in 
Brazil: ,,Matraca‘*). The rattling noise is heard as soon as a butterfly catches sight of another one, but also 
in the pursuit of invaders into the district of impatiently waiting males. Another peculiarity consists in the 
upper surface of the Ageroniidi exhibiting a lichenoid or trunk-brown protective colour, while the under surface 
often has bright, glaring colours, such as hemochrome, crocus-yellow etc. Consistent with this is also the atti- 
tude while being at rest, about similar to that of a Boarmia; the butterfly sits with flatly spread wings clinging 
to a trunk and never claps the wings together above the back, like the other day-butterflies. There are often 
dozens of butterflies sitting on one trunk. When being chased up, they furiously whirl round the trunk and 
then generally settle on that side of the tree being opposite to the pursuer’s. When flying away they glide along 
silently, but sometimes they were flying around me with a rattling noise, when I was standing in an open space, 
and when I kept quiet, they settled down on my grey suit with their heads down and their wings spread out. 
— The organ by which they create the sounds, was of course first searched for in the veins. In the very much ratt- 
ling A. feronia there is, however, no thickening of the veins found in the basal part of the wings, but the 
forewing shows the discocellulars thickened to a strong, horny listel, just like the median and the radials at 
the place where they are joined with the discocellulars. On the under surface of the wings, the connecting 
point of the upper discocellular with the subcostal may be raised to a veritable knob which must certainly be 
suspected to be degenerated in such a peculiar way by the transformation into an instrument. In opposition 
to this fact, REVERDIN on examining the genitals, has recently discovered an organ consisting of 2 spiny points, 
at the abdominal margin of Aperonies, in which he suspects the creator of the sounds. — The larvae, as far 
as is known, live on Dalechampia-species; they exhibit 2 thin, slightly bent horns on the head and on the back 
single spines developed at the end to branched spikes; the pupa itself has on the head two long divergent appen- 
dages (hare’s ears), but otherwise no conspicuous appendages. The butterflies are fond of resting on the trees 
of avenues and on the palmtrees bordering the roads, on Oreodoxa being widely spread in the tropical American 
pleasure-grounds, on Embauba-trees and Bombax. 
51. Genus: EKetima Dol. 
Pretty small brown butterflies with white band of the forewing and lichenoid markings, beneath without 
glaring colours. The first subcostal vein of the forewings branches off immediately before, the second behind 
the cell-end; the upper discocellular is quite short, the middle one curved, the lower one stunted. The most 
conspicuous parts in the butterfly are the very long middle- and especially hind-legs the shins of which, 
as well as the femurs and tarsi are very much elongated. By stretching these legs the butterfly resting head 
downwards on trunks, raises the anterior body, while the distal margins of the wings are closely appressed 
to the bark of the trunk. The larva of the forms greatly resembling one another, lives on Dalechampia; 
