i8 
SOUTH-AFRICAN BUTTERFLIES. 
inclined position. Going on to the Erycinidce^ the males of which have 
the fore-tarsi smooth and reduced to two joints (or even one only), there 
appear first a series of girt pupas, then one of ungirt but rigidly- 
inclined pupae, and finally — in the Sub-Family Libythceinm — pup^ sus- 
pended freely by the tail. This last mode of suspension is universal 
in the Nymphalidce^ the perfect insects of which display reduced and 
atrophied fore-legs in both sexes. In the males of these tetrapod or 
" four-legged " Butterflies, and even in the females of some in the Sub- 
Families DanainoB and Satyrince, the fore-legs are so reduced as to be 
hardly noticeable in their folded position against the prothorax. 
In the neuration the most serviceable distinctive characters are to 
be found in the number and points of origin of the branches or nervulcs 
of the subcostal nervure of the fore-wings, and in the completeness or 
otherwise of the transverse or oblique disco-cellular nervules, which 
serve to connect, in both fore and hind wings, the discoidal or radial 
nervules (the main trunk or nervure of which is atrophied in all Butter- 
flies), with the subcostal nervure above them and the median nervure 
below them.-^ The short disco-cellular nervules in question constitute 
the outer limit of the so-called discoidal cell, lying between the subcostal 
and median nervures ; when the lowest of these nervules is developed 
the discoidal cell is said to be closed, and when it is obsolete or rudi- 
mentary the cell is styled open. 
As regards the presence of a second pair of spurs on the tibige of 
the hind-legs, this is among Butterflies a feature of the Hes'peridce only. 
But this aberrant and curious family, by common consent the nearest 
to Moths, possesses a kindred feature common and peculiar to itself 
and the Papilionincc only, viz., a process or expansion, sometimes 
acuminate, on the inner side of the tibia of the fore-legs. 
Further aids to the scientific arrangement of the Butterflies are to 
be found in the length and gradual or abrupt clavation of the antennse ; 
the size and clothing of the labial palpi ; the smoothness or downiness 
of the compound eyes ; the size, shape, clothing, and texture of the 
wings, and the prevalent colouring and pattern of the latter organs. 
The two last named of these are of considerably more weight in the 
Lepidoptera than in the other Orders of Insects ; the coloured scales 
on the immense area of the wings being apparently affected in their 
arrangement and tints in direct relation to any modification arising 
in the species, and so serving, as Mr, Bates has well observed,^ as 
natural tablets on which are registered all the changes of organisation, 
however small. 
The claws at the end of the tarsi, with their curious appendages 
(first illustrated carefully by M. Doyere in 1843, and afterwards so 
^ I adopt Doubleday's modification of Lefebvre's analysis of the system of neuration in 
the Lepidoptera, given by the former in the Transactions of the Linnean Society, 1 845, vol. 
xix. pp. 477-485, and in Genera of Diurnal Lepidoptera, i. p. 31 (1847). 
^ Naturalist on the Amazons, 2d edit., p. 413. 
