290 



THE YOUNG 



NATURALIST. 



Variation. — This little butterfly varies 

 in the absence or presence of a row of orange 

 spots at the hind margin, on the upper side 

 of all wings, of a black or white spot at the 

 centre of the fore wings, and of black centres 

 to the spots on the underside. The band of 

 orange spots used to be considered charac- 

 teristic of specimens from the South of Eng- 

 land, but it is often well developed on those 

 taken in the North of England. The type 

 may be considered to be those butterflies 

 that have these spots very distinct, a black 

 spot at the disc of the fore wings, and black 

 centres to the white spots of the underside. 

 The var. Artaxerxes, Fab. has the orange 

 spots wanting or very indistinct, the disc 

 spot white, and the white spots of the under- 

 side without black centres. The var. Sal- 

 macis, Steph. is an intermediate form ; has 

 the orange spots less vivid than the type, 

 a black disc spot, but the white spots of 

 the underside without black centres. 

 Staudinger names other two forms : Allous, 

 Hb.,and JEstiva, Hb.,the former all fuscous 

 above, and the latter (a variety of the second 

 brood), brown on the underside — of this 

 form I have taken a specimen this season. 

 Kirby gives another, Callida, Bell., occuring 

 in Corsica ; I do not know how it is dis- 

 tinguished. Aberrations sometimes occur 

 in which the spots on the underside vary. 

 I have one that has the central spot only, 

 one without this is figured by Mr. Mosley 

 in his Illustrations, where there is also a 

 figure of a specimen taken by Mr. Carr, in 

 which the spots are elongated into streaks, 

 a form of variety noticed in several other 

 species of the genus. 



Note. — It cannot cause surprise that 

 this little butterfly has had many names. 

 Lewin, in 1795, called it Idas, which name 

 was also used in 1803, by Haworth. 

 Stephen's, in 1831, adopted the name A testis, 

 S.V., by which it continued to be known for 

 a long time, and which is still used in many 



catalogues. Newman, in 1871, uses Esper's 

 name of Medon. Staudinger in the same 

 year proposed to call it Astrarche, Berg- 

 strasser ; while Kirby, also in 1871, calls it 

 Alexis, Scop. If the Alexis of Scopoli really 

 be the species under consideration, this name 

 must stand, as it dates from 1763. If not, 

 Esper's name of Medon has priority over 

 Astmrche, the former dating from 1766, and 

 the latter from 1779. Agestis was first used 

 in 1776. 



WINGS OF BUTTERFLIES. 



See Plates 23 and 25. 



In order that our young readers may 

 understand something beyond the mere 

 names of species, if they disposed, we have 

 taken the liberty of copying in plates 23 and 

 25, a " plate of details," from the well-known 

 work "The Genera of Diurnal Lepidoptera," 

 by Messrs. Doubleday, Westwood, and 

 Hewitson. We thought it better to copy 

 the figures from a standard work like this, 

 rather than give others, though possibly 

 some might have beeen selected that would 

 be more closely related to our British 

 species. We wish our readers to know the 

 names of what have been, not very appro- 

 priately, called the " wing bones" of Butter- 

 flies, and by a careful comparison of these 

 figures, we hope they will learn something 

 of their construction. 



We will first give the names used for the 

 various "bones," and the references. 

 Figure i. and iii. pi. 23, v. and vii. pi. 25, 

 represent the fore wings of four different 

 butterflies. 



a Costal nervure 



b Sub-costal nervure 



bi, i>2t 63, 64, 65, Sub-costal nervules 



ci, ci, Discoidal nervules 



d Median nervure 



di, d2, ^3, Median nervules 



e Sub-median nervure 



