22 
SOUTH-AEEICAN BUTTERFLIES. 
Hi. Subcostal nervure of fore-wings with three (in one species only- 
two) branches radial nervule of hind-wing somewhat dis- 
connected from subcostal nervure, being united to it only by 
an imperfect transverse nervule. 
Sub-Family 4. — Erycinijice. 
BBB. Tarsi of first pair of legs in male wanting one or both claws, 
but spined beneath ; perfect in female. 
Family III. — LYC^NiDiE. 
BDBB. Tarsi of first pair of legs perfect in both sexes. 
Family lY. — PAPiLiONiDiE. 
k. Tarsal claws bifid ; inner margin of hind-wings prominently 
rounded, 
Sub-Family i. — Pierince. 
H: Tarsal claws simple ; inner margin of ' hind-wings hollowed ; 
tibiae of first pair of legs with a small process on their inner 
edge. 
Sub-Family 2. — Papilioninoe. 
AA. Antennse wide apart at origin ; tibise of hind pair of legs with an 
additional pair of spurs rather beyond the middle. 
Family V. — HESPERiDyE. 
3. Geographical Distribution. 
Taken as a group, Butterflies may be described as of almost uni- 
versal distribution over the earth, there being scarcely any known spots ^ 
(except in the Antarctic lands and islands) where in the summer, at 
least in favourable years, some species do not occur. In the highest 
northern latitudes yet explored various kinds have been met with, even 
Grinnell Land, in the extreme north of America (between lat. 78° and 
83°), having yielded five species belonging to three families.^ The 
most southern known station of Butterflies is at the other extremity of 
America, several kinds inhabiting Tierra del Fuego, on the shore of the 
Strait of Magellan. These remote outposts are, however, highly un- 
favourable to butterfly existence, which finds its highest development 
in the Tropical Regions, and, speaking generally, thins out and wanes 
in proportion to distance from the equatorial belt. In the same way, 
as a broad rule, these insects become scarcer as a higher altitude is 
reached, although there are many peculiar and abundant alpine forms ; 
and where flowering vegetation dies out, the limit of the actual habitat 
of Rhopalocera is found, seeing that the larvas are exclusively, and the 
^ Iceland is perhaps one ; Dr. Staudinger, the well-known lepidopterist, having found no 
butterflies among the thirty-three species of Lepidoptera he collected in that island. But I 
believe he only collected during a single season ; and several butterflies have been reported 
as inhabiting Iceland. 
2 See M'Lachlan's Report on the Insects collected on the Arctic Expedition of the 
"Alert" and "Discovery" in 1875-76 [Journ. LUm. Soc, Zool., xxv. p. 98, 187S). 
