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EXPLANATION OF PLATE A. 



WING NEURATION AND OTHER STRUCTURAL FEATURES OF BUTTERFLIES. 



1. In this Plate the neuration of the fore-wmg and hind-wing of butterflies of each Family 

 and Sub-Family found in Southern Africa is rei^resented, as are also the head and legs of some 

 of them. 



The species here illustrated have been purposely selected as the commonest and most easily 

 procufable among the more characteristic representatives of the several groups, with the 

 exception of Libiithca Laius (fig. 5), which is the only South African member of its Family, 

 and Rhopalocampta KeitMoa (fig. 9), which from its large size afforded more convenience of 

 illustration than the commoner small species of Hesperidse. 



The figures of wing neuration are in every case of the natural size. Those of the head are 

 all somewhat magnified, except fig. 8a (Papilio Dcmoleus) and fig. 9A (RhojMlocampta KeitMoa). 

 The figures of the legs are all of the natural size except fig. iB, a' (JJanais Chrysipiyus), which is 

 considerably enlarged. 



' The species representing the several Families and Sub-Families are the following, viz. : — 



Family NYMPHAliDiE — 



Sub-Family BavaincB . . Figs, r, lA, iB. Danais Chrysippus. i 



,, Satyrinte . . ,,2, 2A. Pseudonympha Sabacus. i 



„ AcrcBinoi . . ,, 3, 3A. Acrcea Horta. S 



,, Nymphalince . Fig. 4. Pyrameis CarduL 6 



Family EEYCiNiDiE — 



Sub-Family Libythceince . . Figs. 5, 5A. Lihythea Laius. 9 

 Family LYC^NiDiE . . . . ,,6, 6a. Lyccena Asteris. i 



,, PAPILIONIDiE — 



Sub-Family Pierince . . Fig. 7. Pieris Hellica. i 



,, Papilionince . . Figs. 8, 8a, 8b. Papilio Demoleus. i 



Family Hespeeid^ . . . ,,9, 9A. Rhopalocampta Keithloa. ? 



The sign 6 denotes the male, the sign ? the female. 



2. In the figures of Wing Neukation, the letter and numbers attached to a particular 

 nervure and its nervules (or branches) are uniform throughout, and apply to both fore and hind 

 wings. In fig. 8 (Papilio) advantage has been taken of its large size to add the names of the 

 various marginal parts and chief areas of the wings, such as base, casta, hind-margin, discoidal 

 cell, &c., which apply to all butterflies alike. The names of the uervures and nervules, and the 

 letters and numbers indicating them, are as follows, viz. : — 



aa. Costal nervure. Simple, without nervules. 1 



b. Subcostal nervure : bi, b2, b3, b4, b5, subcostal nervules. There are usually five sub 

 costal nervules in the forc-iving, but sometimes (see fig. 6) four only, or more rarely 

 (see fig. 7) three nervules. In the hind-iviny there are invariably only two subcostal 

 nervules. 



CI, 02. Discoidal or radial nervules. These nervules are held to be persistent branches of 

 a discoidal nervure traversing the discoidal cell, still found in many moths [Hete- 

 rocera) but wanting in all butterflies, except for a trace or rudiment in rare instances 

 at the outer extremity of the discoidal cell (see figs, i and 9). There are two of 

 these nervules in the fore-iving, but only one in the hind-iving. The latter is, how- 

 ever, badly developed or wanting altogether in the Family Hesperidce (see fig. 9). 



d. Median nervure: di, d2, d3, median nervules. There is no variation in the number of 



these nervules. 



e. Suhmedian nervure. Simple, without nervules. 



f. Internal nervure. Simple, without nervules. This short nervure is usually wanting in 



the fore-wing. When present it usually terminates (see Danais, fig. i ; and Libythea, 

 fig- 5) by junction with the submedian nervure. In Papilio (fig. 8) it is best 

 developed, and terminates independently on the inner-margin. In the hind-wing it 

 is usually much more prominent, and always independent, terminating at some point 

 on the inner margin ; but in Papilio it is altogether wanting. 

 gi, g2, g3. Disco-cellular nervules. These short transverse or oblique nervules connect 

 the discoidal or radial nervules with each other, and also with the subcostal and 

 median nervures (or one of their nervules) respectively above and below them. In 

 the fore-wing the first (upper) nervule is generally very short, and sometimes (as iu 

 Pieris, fig. 7) absent entirely, the first (upper) discoidal or radial nervule being 

 directly united with the subcostal nervure ; while the third (lower) nervule is some- 



1 The base of this nervure, in common with that of the median and submedian nervures iu some 

 genera, is in many Sati/rince and some ifymphaliiM swollen or inflated (see fig. 2, aa) in the fort-winy 

 only. I ; > '.' -1 .' . • 



