_Under Side._ Tongue obsolete. Palpi, breast, abdomen, and wings brown, as on the upper side; the latter immaculate, except a dark patch on each wing near the shoulders. Margins of the wings slightly dentated. PLATE XV. [Illustration] NYMPHALIS ERITHONIUS. Plate XV. fig. 1, 2. ORDER: Lepidoptera. SECTION: Diurna. FAMILY: Nymphalidæ, _Swains_. GENUS. NYMPHALIS, _Latr. God._ Papilio (Dan. Festivi), _Linn. Drury_. NYMPHALIS MEDON. Alis dentatis, supra fuscis; anticis utrinque fasciâ obliquâ luteâ, apice albo; posticis fasciâ violaceo-coerulescenti, singulis subtùs punctis tribus. (Expans. Alar. 3 unc. 7 lin.) SYN. Papilio (Nymph.) Erithonius, _Fabr. Ent. Syst._ III. 1. _p._ 82. _No._ 255. _Latr. & God. Enc. Méth._ ix. _p._ 390. _No._ 142. (Nymphalis Er.) Papilio (Dan. Festivi) Eupalus, _Fabr. Ent. Syst._ III. 1. _p._ 48. _No._ 148. Papilio Harpalyce, _Cram. pl._ 145. _fig._ D. E. Papilio (Equ. Achiv.) Medon, _Drury, App. vol._ 2. (Exclus. Syn. _Linn. & Fabr._) HABITAT: Sierra Leone. _Upper Side._ Antennæ black, lighter at the tips. Head black. Thorax and abdomen dark brown. Anterior wings dark red brown, tipped with white; but next the shoulders of a purplish hue, with a dark yellow streak near the tips, extending obliquely from the anterior towards the external edge. Posterior wings also red brown; but towards the middle and shoulders of a purplish blue, which they reflect more or less according to the position they are held in. _Under Side._ Palpi and breast yellow. Anterior wings olive brown, tipped with white; but along the external edges of a hazel colour, and near the shoulders having three round black spots on each. Posterior wings similar to the anterior, being of a brown olive, variegated, and clouded, with three small spots placed near the shoulders, as in the superior ones. All the wings are a little dentated. There are several African species closely allied to the present insect, which was regarded by Drury as the Medon of Linnæus. I have followed the Encyclopédie Méthodique in rejecting this reference; although it will be seen that the Linnæan description of that insect, "alis supra nigris primoribus fascia lutea apiceque albo; posticis disco coerulescentibus," does not disagree with the character of this insect.